Honda Giken Kogyo Kabushiki Kaisha

Honda Giken Kogyo K.k.

Izumi Sugiyama

Chihaya Sugimoto

Susumu Toki

Shigemasa Kajiwara

Masakazu Kinoshita

Hideki Saito

Toshiyuki Satou

Kensuke Nakamura

Masayasu Sakata

Yoshihito Tsuji

Masato Matsuki

Hirosuke Niwa

A plate-shaped gasket is inserted between a plurality of parts with an edge of the plate-shaped gasket offset such that portions of mutually joining surfaces of the plurality of parts to be joined to each other (a cylinder block and a cylinder head , as well as a chain cover and a sprocket casing portion in the embodiment) directly oppose each other, and a liquid gasket is filled in a gap G formed by the directly opposing portions of the plurality of parts and the offset edge (an inner peripheral edge of a chain accommodating hole ) of the plate-shaped gasket. As a result, since the thickness of the liquid gasket can be determined by the thickness of the plate-shaped gasket, it becomes unnecessary to form a recessed portion for storing the liquid gasket by machining, so that the number of manufacturing steps is prevented from increasing.

Sealing structure

A tensioner for a camshaft driving chain (a plunger device,shown in the first embodiment of the invention) and a hydraulic control valve,are disposed close to each other. An oil passage,for supplying an oil pressure to the tensioner is caused to branch off from a downstream side of an oil filter,provided at an inlet port,of the hydraulic control valve. With this construction, the arrangement of the oil passage can be simplified, and therefore not only can man hours required for forming the oil passage be reduced, but also the number of components required can also be reduced by commonizing the oil filter. Accordingly, it is possible to provide an improved assembling arrangement for a tensioner and a hydraulic control valve in an internal combustion engine without involving an increase in production costs.

Assembling arrangement for tensioner and hydraulic control valve

In an intake port structure in an internal combustion engine, an edge portion is formed on a lower surface of an intake port at a location immediately upstream of an intake bore 7. The angle .theta. formed by the center line L of the intake port with respect to a deck surface is set smaller than the angle .theta..sub. formed by an exhaust valve seat provided in a pent roof of a combustion chamber with respect to the deck surface. Further, if the height of an apex of the pent roof of the combustion chamber is represented by H.sub.0, and an intersection between an extension of the center line L of the intake port 5 and a straight vertical line L.sub.0 passing through the apex of the pent roof of the combustion chamber to intersect the deck surface at a right angle is represented by P, the height H of the intersection P is set so that a relation, H.sub.0 &gt;H&gt;2H.sub.0 /3 is satisfied.

Intake port structure in an internal combustion engine

An oil pan for an internal combustion engine is made of cast aluminum alloy and has a first flange for attachment to the cylinder block and a second annular flange for attachment to the transmission case. Access holes near a bottom end of the second annular flange allow access to the heads of mounting bolts extending through the first flange. The first flange can be securely clamped to the opposing mounting of the cylinder block because all of the mounting bolts can directly clamp the first flange onto the mounting surface. Annular ribs surround the access holes and are connected together by a connecting rib so as to ensure a sufficient rigidity of the second flange. As a result, the sealing performance can be readily ensured and a vibration free power structure can be achieved.

Oil pan for an internal combustion engine

A valve operating mechanism for an internal combustion engine for varying the operation of the valve dependent on engine operating conditions. A first rocker arm movable to follow a first cam and a second rocker arm movable to follow a second cam corresponding to a higher speed operating condition than that of the first cam are pivotally supported on a rocker arm shaft. A first connection switching device capable of switching the connection and disconnection between the third and first rocker arms and a second switching device capable of switching the connection and disconnection between at least one of the first and third rocker arms and the second rocker arm independently from the first connection switching device, are disposed at locations displaced circumferentially relative to the rocker arm shaft. Thus, it is possible to dispose a trigger mechanism and to dispose3 roller followers coaxially with the connection switching device, while avoiding the increase in width of the three rocker arms along their swinging axes.

Valve operating device for an internal combustion engine

A valve operating mechanism for an internal combustion engine for varying the operation of the valve dependent on engine operating conditions. A first rocker arm movable to follow a first cam and a second rocker arm movable to follow a second cam corresponding to a higher speed operating condition than that of the first cam are pivotally supported on a rocker arm shaft. A first connection switching device capable of switching the connection and disconnection between the third and first rocker arms and a second switching device capable of switching the connection and disconnection between at least one of the first and third rocker arms and the second rocker arm independently from the first connection switching device, are disposed at locations displaced circumferentially relative to the rocker arm shaft. Thus, it is possible to dispose a trigger mechanism and to dispose roller followers coaxially with the connection switching device, while avoiding the increase in width of the three rocker arms along their swinging axes.

Growing community of inventors

Saitama, Japan

Izumi Sugiyama