Patent attributes
An internal combustion engine includes: a main combustion chamber; an intake port connected to the main combustion chamber; an exhaust port connected to the main combustion chamber; a sub-chamber; and a spark plug in the sub-chamber. The sub-chamber is provided between the intake opening portion and the exhaust opening portion and connected to the main combustion chamber through a plurality of communication holes. The communication holes include a first communication hole provided on the intake opening portion side, and a second communication hole provided on the exhaust opening portion side. The first communication hole is closer to a piston than the second communication hole is. The first communication hole is inclined to be closer to the piston as the first communication hole is positioned toward the inside from the outside of the sub-chamber.
