US 11,753,985 B2
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. 15, 2022, as Appl. No. 17/987,473.
Claims priority of application No. 2021-198056 (JP), filed on Dec. 6, 2021.
Prior Publication US 2023/0175426 A1, Jun. 8, 2023
Int. Cl. F02B 19/10 (2006.01)
CPC F02B 19/1023 (2013.01) [F02B 19/108 (2013.01); F02B 19/1014 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An engine comprising:
a main combustion chamber including a cylinder block, a cylinder head, and a piston;
a pre-chamber having a plurality of injection holes that open into the main combustion chamber; and
a spark plug that ignites an air-fuel mixture in the pre-chamber,
wherein a compression ratio ε of the main combustion chamber is not less than 14 and not more than 24, and
an index St·ε that is a product between a total cross-sectional area St of the plurality of injection holes and the compression ratio ε is not less than 0.1496 cm2 and not more than 0.8449 cm2.