US 12,246,809 B2
Vessel propulsion apparatus, vessel, vessel engine, and exhaust structure of vessel engine
Shinya Kasai, Shizuoka (JP); Koichi Nakayama, Shizuoka (JP); and Jiro Fukuoka, Shizuoka (JP)
Assigned to YAMAHA HATSUDOKI KABUSHIKI KAISHA, Shizuoka (JP)
Filed by YAMAHA HATSUDOKI KABUSHIKI KAISHA, Iwata (JP)
Filed on Oct. 20, 2022, as Appl. No. 17/969,846.
Claims priority of application No. 2021-185987 (JP), filed on Nov. 15, 2021.
Prior Publication US 2023/0150635 A1, May 18, 2023
Int. Cl. B63H 20/24 (2006.01); F01N 13/10 (2010.01)
CPC B63H 20/245 (2013.01) [F01N 13/10 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A vessel propulsion apparatus comprising:
an engine; and
a propulsion unit to be driven by the engine; wherein
the engine includes:
a plurality of cylinders arranged in series and each including a combustion chamber;
a plurality of exhaust ports respectively connected to the combustion chambers of the plurality of cylinders and curved in a predetermined downstream direction of a flow of exhaust gases to allow the exhaust gases to flow out from the combustion chambers;
a collecting exhaust pipe integral with the plurality of exhaust ports and extending in the downstream direction to allow the exhaust gases in the plurality of exhaust ports to flow in the downstream direction; and
a plurality of connector portions that individually connect the plurality of exhaust ports to the collecting exhaust pipe, and each of the plurality of connector portions includes a first concave portion at an inner surface thereof and a second concave portion located in a region of an inner surface of the collecting exhaust pipe, and the first concave portion and the second concave portion do not extend through the plurality of connector portions.