US 12,104,562 B2
Boat propulsion device
Kazuhiro Hara, Shizuoka (JP); Toru Takahashi, Shizuoka (JP); Norihito Tabata, Shizuoka (JP); Kazuki Sano, Shizuoka (JP); and Shinsaku Soda, Shizuoka (JP)
Assigned to YAMAHA HATSUDOKI KABUSHIKI KAISHA, Shizuoka (JP)
Filed by YAMAHA HATSUDOKI KABUSHIKI KAISHA, Iwata (JP)
Filed on Feb. 23, 2023, as Appl. No. 18/113,230.
Claims priority of application No. 2022-173339 (JP), filed on Oct. 28, 2022.
Prior Publication US 2024/0141855 A1, May 2, 2024
Int. Cl. F02M 35/10 (2006.01); B63H 20/24 (2006.01); F01N 13/10 (2010.01)
CPC F02M 35/1015 (2013.01) [B63H 20/245 (2013.01); F01N 13/10 (2013.01); F02M 35/10144 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A boat propulsion device comprising:
an internal combustion engine; and
an intake device to supply air to the internal combustion engine; wherein
the intake device includes:
a main intake pipe including a first intake pipe and a second intake pipe including an upstream end connected to a downstream end of the first intake pipe and extending at an angle with respect to an axial direction of the first intake pipe and through which the air supplied to the internal combustion engine flows; and
an extension pipe extending directly from, and in communication with, a connection between the downstream end of the first intake pipe and the upstream end of the second intake pipe and including a resonance chamber therein; and
the extension pipe includes a partition wall that closes the extension pipe except for a portion of the extension pipe adjacent to the main intake pipe.