Nissan Motor Company Limited

Other

Unisia Jecs Corporation

Shunichi Aoyama

Shinichi Takemura

Katsuya Moteki

Ryosuke Hiyoshi

Kenshi Ushijima

Takanobu Sugiyama

Tsuneyasu Nohara

Makoto Kobayashi

Seinosuke Hara

Manabu Kato

Motohiro Shinzawa

Shinichiro Kitada

Noboru Hattori

Isaya Matsuo

Nobukazu Kanesaki

Yoshiki Sekiya

Yoshiaki Tanaka

Hirofumi Tsuchida

Koji Hiraya

Masayuki Tomita

Hiroya Fujimoto

Tsuyoshi Arinaga

Kazuyuki Miisho

Makoto Nakamura

Hiroshi Fujii

Toru Noda

Toru Fukami

Hideaki Mizuno

Yoshimasa Hayashi

Yoshihiko Yamada

Keisuke Takeda

Naoki Okamoto

Takayuki Arai

Naoki Takahashi

Akinori Suzuki

Tsutomu Hibi

Shin Ishizaki

Tetsuro Goto

Ryousuke Hiyoshi

Eiji Murata

Akira Ohnuki

Ryosuke c/o Intellectual Property Of Nissan Motor Co Ltd Hiyoshi

A variable valve system for an internal combustion engine includes a drive shaft, a drive cam provided on the drive shaft, a link arm fitted on the outer periphery of the drive cam such as to rotate relative to the drive cam, a crank-shaped control shaft including a main shaft and an eccentric cam, an oscillating arm rotatably attached to the eccentric cam and oscillated by the link arm, and an oscillating cam connected to the oscillating arm via a link rod so as to actuate a valve. Lubricant is communicated from a main lubricant flow path in the drive shaft through three lubricant paths to sliding contact areas between the drive cam and the link arm, between the pin of the oscillating arm and the link arm, and between the eccentric cam and the oscillating arm.

Variable valve system for internal combustion engine

A valve operating device that opens and closes a valve of an internal combustion engine by driving a valve stem in an axial direction includes a rocker cam that rocks in accordance with a rotation of a drive shaft and has a driving cam portion and a lift restricting cam portion; a cam follower that lifts the valve by contacting the driving cam portion slidingly; and a restricting member that prevents the cam follower from separating from the driving cam portion in cooperation with the lift restricting cam portion. A gap is formed between the restricting member and the rocker cam in a state where the cam follower is in contact with the driving cam portion and disappears such that the restricting member and the rocker cam come into contact with each other only when the cam follower separates from the driving cam portion.

Valve operating device for internal combustion engine

A multi-link engine has a piston coupled to a crankshaft to move inside an engine cylinder. A piston pin connects the piston to an upper link, which is connected to a lower link by an upper link pin. A crank pin of the crankshaft rotatably supports the lower link thereon. A control link pin connects the lower link to one end of a control link, which is connected at another end to the engine block body by a control shaft. The crank pin has a center arranged on a straight line joining centers of the upper link pin and the control link pin such that an angle formed between the straight line and a horizontal axis that is perpendicular to a center axis of the cylinder and that passes through an axial center of a crank journal is the same for at top dead center and at bottom dead center.

Multi-link engine

A multi-link engine has a piston coupled to a crankshaft to move inside an engine cylinder. A piston pin connects the piston to an upper link, which is connected to a lower link by an upper link pin. A crank pin of the crankshaft rotatably supports the lower link thereon. A control link pin connects the lower link to one end of a control link, which is connected at another end to the engine block body by a control shaft. The upper link has an upper link axis that forms an angle with the cylinder axis, as viewed along a crank axis direction of the crankshaft, such that the angle reaches a minimum when a crank angle of the engine is within a range where the bottom end of a piston skirt is positioned below a topmost part of the bottom end of the cylinder liner.

An engine intake control apparatus for an engine that comprises at least one combustion chamber operatively connected to an intake port and an intake valve associated with each intake port, wherein the intake valve is adapted to open and close the intake port is disclosed herein. The intake control apparatus comprises a variable valve operating mechanism and a controller. The variable valve operating mechanism is configured and arranged to selectively change a valve closing timing and a valve lift amount of the intake valve. The controller is configured and arranged to control the variable valve operating mechanism when the engine is in a low load condition. The valve closing timing is determined such that an actual compression ratio of the engine is reduced relative to the actual compression ratio when the engine is operating in a high load condition. The valve lift amount is smaller when the engine is in the low load condition relative to the valve lift amount when the engine is in the high load condition. A method for controller an engine is also disclosed.

Intake control apparatus for an engine and method

A multi-link engine has a piston that moves inside a cylinder. A piston pin connects the piston to an upper link, which is connected to a lower link. A crank pin of a crankshaft supports the lower link thereon. The lower link is pivotally connected to one end of a control link, which is connected at another end to the engine block body by a control shaft. The control shaft is lower than a crank journal of the crankshaft, and disposed on a first side of a plane that is parallel to a cylinder center axis and that contains a center rotational axis of the crank journal. The cylinder center axis is located on a second (i.e., opposite the first side) plane. The control link has a center axis that is parallel to the cylinder center axis when the piston is near top and bottom dead centers.

In a reciprocating piston engine employing a variable compression ratio mechanism linked to a reciprocating piston for variably adjusting a geometrical compression ratio by varying at least a piston top dead center position, so that the top dead center position obtained at a low geometrical compression ratio is set to be lower than that at a high geometrical compression ratio, responsively to a controlled variable, a controller is configured to set a target compression ratio to a high value at low engine load operation, and to a relatively low value at high engine load operation. A substantially entire area of a crown of the piston, defining a part of a wall surface of a combustion chamber, is formed of a non-metallic material having a higher heat-insulating and heat-reserving property as compared to a base structural material of each of the combustion chamber and the piston.

Internal combustion engine

An internal combustion engine includes a piston adapted to reciprocate in a cylinder. The piston includes a first portion, a second portion, and a third portion. The first portion of the piston forms a crown surface of the piston, the second portion of the piston forms a piston ring groove of the piston with the piston ring groove arranged and configured to receive a piston ring, and the third portion of the piston forms a crankcase side surface of the piston with the crankcase side surface facing a crankcase of the engine. The second portion of the piston is formed of a material having a higher thermal conductivity than a material forming the first portion of the piston and a material forming a third portion of the piston.

Internal combustion engine with improved thermal efficiency

There is provided a system for controlling an intake valve of an internal combustion engine, including a variable valve mechanism having a control shaft to continuously vary a valve lift amount of the intake valve according to a rotational angle of the control shaft and an actuator to drive the control shaft, and a control unit that controls the actuator so as to set the control shaft to a first rotational angle position at which the valve lift amount takes a first value during an engine idling period and to a second rotational angle position at which the valve lift amount takes on a second value larger than the first value to provide a required intake quantity to start the engine during a time from the beginning of an engine speed decrease period, through an engine stop period, until the completion of a cranking period of the engine.

Intake valve control system and method for internal combustion engine

An internal combustion engine includes a piston () and a crankshaft (). The crankshaft () includes: a journal (A) as a rotation center; a crank pin (B) that is located eccentrically with respect to the journal (A) and rotates integrally with the journal (A), the crank pin () connecting the piston () to the crankshaft (); and a counter weight (C) that is located eccentrically with respect to the journal (A) in a direction opposite to the crank pin () and rotates uniformly with the journal (A). A cutout () through which the counter weight (C) passes is formed in a wall () of a cylinder bore that accommodates the piston () so as to be free to move reciprocally along the wall (). As a result, the bottom dead center position of the piston can be lowered, and the overall height of the engine can be decreased.

Engine overall height reduction

A lower link for a piston crank mechanism of an internal combustion engine includes an upper section, a lower section, and a crank pin bearing section disposed between the upper section and the lower section, and mounted on a crank pin of a crank shaft. One of the upper section and the lower section is formed with a bolt inserting hole. The other of the upper section and the lower section is formed with an internal thread portion including an open end. One of the bolts passes through the bolt inserting hole, is screwed into the internal thread portion, and includes an end bared from the open end which is formed in a surface perpendicular to a bolt center axis. The other of the upper section and the lower section includes a recessed portion formed in the surface to divert a stress transmitting path.

Lower link for piston crank mechanism of internal combustion engine

An internal combustion engine includes a piston reciprocating in a cylinder; a crankshaft; and a multilink piston-crank mechanism linking the piston with the crankshaft. The multilink piston-crank mechanism includes an upper link having a first end connected with the piston by a piston pin; a lower link mounted rotatably on a crankpin of the crankshaft and having a first end connected with a second end of the upper link by a first connection pin; a control link having a first end connected with a second end of the lower link by a second connection pin; a control shaft connected movably with a second end of the control link and configured to rotate in synchronization with the crankshaft and at a half rotational speed of the crankshaft; and a phase adjusting section configured to variably adjust a phase of rotation of the control shaft relative to the crankshaft in accordance with an operating condition of the engine. The multilink piston-crank mechanism is configured to variably control a piston stroke characteristic of the engine.

A link mechanism usable for a variable compression ratio mechanism of an internal combustion engine includes first and second links pivotally connected by a pin inserted through cylindrical first and second pin boss portions of the first and second links. Each of the first and second pin boss portions includes a circumferentially extending first narrow section, and a circumferentially extending first wide section having an axial wall thickness greater than the axial wall thickness of the first narrow section. The wide sections of the first and second pin boss portions are overlapped in an region extending in the axial direction of the pin.

Pin connected link mechanism

A control apparatus for an internal combustion engine includes a variable compression ratio mechanism capable of varying a compression ratio of the engine, a compression ratio setting section that sets a compression ratio to be attained by the variable compression ratio mechanism in accordance with an operating condition of the engine, a knock detecting section that detects a knock occurrence state, an ignition timing learning correcting section that determines a learning correction value of an ignition timing in accordance with the knock occurrence sate, and a compression ratio correcting section that corrects the compression ratio set by the compression ratio setting section in accordance with the learning correction value of the ignition timing. A control method is also provided.

Control apparatus and method for internal combustion engine with variable compression ratio mechanism

Growing community of inventors

Kanagawa, Japan

Shunichi Aoyama