{
  "$type": "site.standard.document",
  "description": "The present teaching provides a spark-ignition engine that achieves an improved thermal efficiency. [0002] The spark-ignition engine includes a cylinder part including a combustion chamber, a piston part, a crankshaft, one exhaust port, one single center tumble port, an offset ignition plug, one…",
  "path": "/patents/1423831",
  "publishedAt": "2022-09-07T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "F02B23/08",
    "YAMAHA MOTOR CO LTD [JP]"
  ],
  "textContent": "The present teaching provides a spark-ignition engine that achieves an improved thermal efficiency. [0002] The spark-ignition engine includes a cylinder part including a combustion chamber, a piston part, a crankshaft, one exhaust port, one single center tumble port, an offset ignition plug, one exhaust valve, and one intake valve. The intake valve has a valve surface part defining the combustion chamber together with the piston part and the cylinder part by closing a gas inlet disposed with an extending area covering a gas outlet. The intake valve opens the gas inlet when the piston part moves toward bottom dead center thereby to cause gas taken into the combustion chamber through the single center tumble port to create a tumble flow, and closes the gas inlet earlier or later than arrival of the piston part at the bottom dead center to allow the spark-ignition engine to have a compression ratio smaller than an expansion ratio thereof.",
  "title": "SPARK IGNITION TYPE ENGINE AND VEHICLE"
}