US 11,655,751 B1
Engine
Yuji Harada, Aki-gun (JP); Kenji Uchida, Aki-gun (JP); Ryohei Ono, Aki-gun (JP); Masayuki Kidokoro, Aki-gun (JP); and Kazuhiro Nagatsu, Aki-gun (JP)
Assigned to Mazda Motor Corporation, Hiroshima (JP)
Filed by Mazda Motor Corporation, Hiroshima (JP)
Filed on Nov. 18, 2022, as Appl. No. 17/989,975.
Claims priority of application No. JP2021-198072 (JP), filed on Dec. 6, 2021.
Int. Cl. F02B 19/10 (2006.01); F02B 19/12 (2006.01)
CPC F02B 19/1014 (2013.01) [F02B 19/1023 (2013.01); F02B 19/12 (2013.01)] 13 Claims
OG exemplary drawing
 
1. An engine comprising:
a cylinder block in which a cylinder is formed;
a cylinder head assembled onto the cylinder block to cover a top of the cylinder;
a piston provided so as to reciprocate inside the cylinder, the piston defining a combustion chamber together with the cylinder block and the cylinder head; and
a spark plug that performs ignition in the combustion chamber,
wherein the combustion chamber includes a sub-chamber that houses an electrode of the spark plug, and a main chamber separated from the sub-chamber by a partition wall having a through-hole, the main chamber having a volume larger than a volume of the pre-chamber, and
wherein a specific ratio obtained by dividing a volume of the sub-chamber by a stroke volume of the cylinder is greater than or equal to 0.00005 and less than or equal to 0.00045.