US 11,834,981 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. 16, 2022, as Appl. No. 17/988,077.
Claims priority of application No. 2021-198058 (JP), filed on Dec. 6, 2021.
Prior Publication US 2023/0175427 A1, Jun. 8, 2023
Int. Cl. F02B 19/10 (2006.01)
CPC F02B 19/1023 (2013.01) [F02B 19/108 (2013.01)] 15 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,
a volume V of the pre-chamber is not less than 0.12 cm3 and not more than 0.328 cm3,
an index V·ε that is a product between the volume V of the pre-chamber and the compression ratio ε is not less than 1.03 cm3 and not more than 5.92 cm3, and
a ratio St/V of a total cross-sectional area St of the plurality of injection holes to the volume V of the pre-chamber is not less than 0.0078 mm−1 and not more than 0.0145 mm−1.