Title:
SPARK-IGNITION ENGINE AND VEHICLE
Document Type and Number:
Japanese Patent JP2021175876
Kind Code:
A
Abstract:
To provide a spark-ignition engine capable of increasing heat efficiency.SOLUTION: The spark-ignition engine comprises: a cylinder part in which a combustion chamber is formed; a piston part; a crankshaft; only one exhaust port; only one single center tumble port; an offset ignition plug; only one exhaust valve; and only one intake valve. The only one intake valve has a valve surface part for defining the combustion chamber together with the piston part and the cylinder part by closing an intake port provided in such a manner that an extended area overlaps an exhaust port. When the piston part is moved to a bottom dead point, the intake port is opened so that a tumble flow can be generated in gas sucked into combustion chamber through the single center tumble port, and the closing of the intake port is set earlier or later than the arrival of the piston part at the bottom dead point, so that a compression ratio of the spark-ignition engine is set lower than an expansion ratio thereof.SELECTED DRAWING: Figure 1
Inventors:
TANOKURA HAYATO
NAGAI YOSHITAKU
NAGAI YOSHITAKU
Application Number:
JP2018132367A
Publication Date:
November 04, 2021
Filing Date:
July 12, 2018
Export Citation:
Assignee:
YAMAHA MOTOR CO LTD
International Classes:
F02D15/00; F02B23/08; F02B31/00; F02D13/02; F02F1/42
Attorney, Agent or Firm:
Patent Service Corporation Tas Meister