公开(公告)号：US20200158006A1

公开(公告)日：2020-05-21

申请号：US16676746

申请日：2019-11-07

Applicant: Mazda Motor Corporation

Inventor： Satoshi IMAMURA ,  Masaki FUKUMA ,  Yasushi NAKAHARA ,  Atsushi INOUE ,  Kota MATSUMOTO ,  Michiharu KAWANO ,  Yuya HONDA ,  Futa NISHI

IPC: F02B23/06

Abstract: A combustion chamber structure for an engine includes a combustion chamber where SI combustion by spark ignition and CI combustion by self-ignition are conducted. A crown surface includes a cavity recessed to have a bowl-shape, and a pair of raised portions. The cavity includes a bottom portion which is a lower region of the recessed part, the bottom portion having an outer circumferential edge which is circular in a top view. With a height of the raised portion relative to a height position of a deepest portion of the cavity being represented as H1 and a diameter of an outer circumferential edge of the bottom portion of the cavity being represented as D, H1/D as a ratio of the height H1 of the raised portion to the diameter D of the cavity is set to be in a range of 0.05 or more and 0.36 or less.