Honda Giken Kogyo Kabushiki Kaisha

Tetsuya Tosaka

Takashi Kanbe

Tadashi Kato

Toshio Shimada

Takashi Akagi

Masao Ishida

Makoto Harada

Toyotaka Kinoshita

Tsuguto Inayama

Masahiko Nakatsura

To provide a multi-cylinder engine for a vehicle, in which a pair of cylinder bore rows, each including a plurality of cylinder bores disposed in parallel to each other, are disposed in such a manner as to be perpendicular to a crank shaft disposed substantially in the horizontal direction. Accordingly, a relatively large space can be ensured under a cylinder head. Cam shafts corresponding to cylinder bore rows are disposed over a pair of planes containing the axial lines of cylinder bores constituting the cylinder bore rows, respectively.

Multi-cylinder engine for vehicle

A bearing metal positioning structure in a split connecting rod with lowered production cost and improved accuracy in positioning the bearing metal. The bearing metal positioning structure includes a pair of bearing metal halves, each of which is formed into a circular arc shape traversing 180 degrees. The pair of bearing metal halves have flat mating planes which abut one another to form a cylindrical bearing metal. A pair of projections are disposed on each of the mating planes at both axial ends so as to project radially outwardly therefrom. Locking grooves to be engaged with the pairs of projections, and additional locking grooves, are integrally die-formed simultaneously with the production of a die-formed body of the split connecting rod.

Bearing metal positioning structure in a split connecting rod

To provide an engine cooling system including a water pump for circulating cooling water in order to cool an engine, and a thermostat provided in the water pump in such a manner as to be openable/closable depending on the temperature of cooling water. The thermostat is provided in the water pump with a reduced number of parts, to thereby reduce the cost, weight and the number of assembling steps. A casing of a water pump is composed of a pump body for rotatably supporting a pump shaft and a pump cover connected to the pump body in such a manner as to cover an impeller fixed to the pump shaft. A thermostat is contained in a containing portion formed in the pump cover in such a manner as to be held between the pump body and the pump cover.

Engine cooling system

To deem a dedicated oil passage unnecessary and therefore make an engine equipped with a plurality of cylinder bores with substantially horizontal axes and provided with transmission mechanisms between a camshaft and crankshaft within a valve chamber more lightweight and compact while returning oil for a valve chamber to a crank chamber. Transmission mechanisms include endless chains wrapped around drive sprockets fixed to one end of a crankshaft and driven sprockets fixed to one end of camshafts. The transmission mechanisms are housed in transmission chambers in such a manner that ends of the transmission mechanisms are made to communicate with the valve chambers and the other ends of the transmission mechanisms are made to face one end in the axial direction of the crankshaft. A return hole causing the lower part of the other end of the transmission chambers to communicate with the crank chamber is provided at the crankcases.

Oil passage structure for returning oil in an engine

A multi-cylinder engine in which a transmission mechanism is provided between a cam shaft linked with intake valves and exhaust valves and a crank shaft rotatably supported by a crank case and a plurality of bearing caps, wherein the transmission mechanism is configured as a chain-type transmission mechanism for making the engine compact. The restriction on the rotatably supporting position of a chain tensioner is moderated and the length of the chain tensioner is set at a relatively large value. The transmission mechanism is configured such that an endless chain, is wound around a drive sprocket, fixed on a crank shaft and a driven sprocket, fixed on a cam shaft. One end portion in the longitudinal direction of a chain tensioner, extending in the running direction of the chain is rotatably supported on one of the plurality of bearing caps in such a manner as to be elastically, slidably in contact with the chain.

Multi-cylinder engine

To provide a multi-cylinder engine in which cam shaft linked with a plurality of intake valves and a plurality of exhaust valves for carrying out intake and exhaust operations for a plurality of combustion chambers is rotatably supported by cam bearing portions provided on the cylinder head and a cam holder fastened to the cam bearing portions. An oil passage capable of supplying oil from an oiling passage provided in the cylinder head is formed in the cam shaft. Oil can be supplied in the oil passage in the cam shaft without restriction in the location of fastening bolts for fastening the cylinder head to the cylinder block. An oiling hole is provided in the cam shaft in such a manner as to be in communication with the oil passage, and an oil groove in communication with the outer end of the oiling hole is formed in a cam bearing portion, provided in the cylinder head, at a position corresponding to one of combustion chambers, in such a manner as to face toward the outer surface of the cam shaft. Furthermore, the oiling passage is in communication with the oil groove.

Structure for lubricating cam shaft in multi-cylinder engine

A horizontally-opposed type engine for a motorcycle, in which a pair of left and right cylinder heads are connected to a pair of left and right cylinder blocks in such a manner that combustion chambers are formed between each of the cylinder blocks containing a plurality of cylinder bores disposed in parallel with the axial lines thereof extending substantially in the horizontal direction and pistons slidably fitted in the cylinder bores; a crank shaft is disposed in such a manner as to be perpendicular to the axial lines of the cylinder bores; and the engine is mounted on the motorcycle with the axial line of the crank shaft extending in the longitudinal direction, wherein the restriction to the bank angle of the motorcycle given by the exhaust pipes is made small and thereby the bank angle is easily ensured. A plurality of exhaust passages, for introducing exhaust gas from the combustion chambers, are provided in each of the cylinder heads in such a manner as to be tilted toward the central side of the motorcycle in the width direction and to be opened downwardly.

Horizontally opposed type engine for motorcycle

To provide a multi-cylinder engine in which a plurality of cylinder bore rows, each including a plurality of cylinder bores disposed in parallel, are disposed in such a manner as to be perpendicular to a crank shaft disposed substantially in the horizontal direction. A plurality of cylinder heads, each forming combustion chambers between pistons slidably fitted in the cylinder bores and the cylinder head, are connected to cylinder blocks corresponding to the cylinder bore rows. Furthermore, a plurality of intake passages and a plurality of exhaust passages respectively in communication with the combustion chambers are provided in the cylinder heads, wherein the structure of an intake system and an exhaust system can be simplified. Intake passages and exhaust passages are provided in the a cylinder head corresponding to a cylinder bore row in such a manner that a relative positional relationship between the intake passages and the exhaust passages in the axial direction of the crank shaft is nearly equal to that between the intake passages and the exhaust passages in the axial direction of the crank shaft.

Growing community of inventors

Saitama, Japan

Tetsuya Tosaka