US 9,810,141 B2 | ||
Internal combustion engine | ||
Tetsuo Omura, Mishima (JP); and Kazuyoshi Abe, Susono (JP) | ||
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota-shi (JP) | ||
Filed by TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota-shi, Aichi-ken (JP) | ||
Filed on Apr. 5, 2016, as Appl. No. 15/91,054. | ||
Claims priority of application No. 2015-078559 (JP), filed on Apr. 7, 2015. | ||
Prior Publication US 2016/0298532 A1, Oct. 13, 2016 | ||
Int. Cl. F02F 1/42 (2006.01); F02B 23/10 (2006.01); F01L 3/06 (2006.01) |
CPC F02B 23/104 (2013.01) [F01L 3/06 (2013.01); F02B 2023/108 (2013.01)] | 6 Claims |
1. An internal combustion engine having a pent roof type combustion chamber configured such that an intake port-side ceiling
surface in which an intake port is open in a cylinder head and an exhaust port-side ceiling surface in which an exhaust port
is open in the cylinder head are inclined to a plane that is perpendicular to a center axis of a cylinder, wherein
a housing space is formed in an opening of the exhaust port to the combustion chamber to be more recessed in the cylinder
head than the exhaust port-side ceiling surface, wherein a bevel portion of an exhaust valve is placed in the housing space
in a valve closed state of the exhaust valve, and a valve contact surface which the bevel portion of the exhaust valve comes
in contact with in the valve closed state of the exhaust valve is formed on an inner wall surface of the housing space, wherein
in a slight lifting state of the exhaust valve that the exhaust valve is lifted up and part of the bevel portion of the exhaust
valve is placed in the housing space, the housing space includes an intake side space that is a clearance between the inner
wall surface of the housing space and the bevel portion of the exhaust valve and is located on an intake port side, and an
exhaust side space that is the clearance and is located on a bore wall surface side of an exhaust port side which is opposite
to the intake side space across the bevel portion of the exhaust valve, and
with regard to an effective passage width of an effective passage that is defined as a linear virtual passage extended from
the combustion chamber through the housing space to inside of the exhaust port in a section extended from the intake port
side to the bore wall surface side of the exhaust port side, the housing space is formed such that the effective passage width
in any location in the intake side space is made smaller than the effective passage width in a corresponding location in the
exhaust side space in the slight lifting state of the exhaust valve.
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