Honda Giken Kogyo Kabushiki Kaisha

Yoshihito Tsuji

Kenji Hirose

Kazuo Yoshida

Masayuki Takahashi

Chihaya Sugimoto

Fuminori Kawashima

Kazuaki Shimoyama

Hideo Ueshima

Izumi Sugiyama

Toshiyasu Komatsu

Keiji Ohtsu

An oil passage structure in an engine includes a first oil passage and a second oil passage. The second oil passage has a hydraulic pressure which is different from that in the first oil passage. The first and second oil passages are provided in engine body in an arrangement where they intersect each other when viewed in projection onto a plane parallel to an axis of the first oil passage. In order to enable the space for disposition of both the oil passages to be reduced to a necessary minimum to provide a reduction in size of the engine body, a cylindrical partition member having annular seal members mounted on its outer surface at opposite ends is fitted into the first oil passage. Thus, an annular intermediate chamber is defined between the outer surface of the partition member and an inner surface of the first oil passage and is sealed at its opposite ends by the seal members. The second oil passage is provided in the engine body in an arrangement where upstream and downstream passage portion thereof communicate with each other through the intermediate chamber.

Oil passage structure in an 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 system in an overhead cam type multicylinder internal combustion engine having three intake-side rocker arms disposed to operate a pair of intake valves and two exhaust-side rocker arms disposed to operate a pair of exhaust valves. The intake-side rocker arms are provided with a connection switchover mechanism capable of switching-over the connection and disconnection of the adjacent in take-side rocker arms. Exhaust-side cams are provided on a cam shaft on opposite sides of intake-side cams which are provided adjacent one another. Two of the intake-side rocker arms and both of the exhaust-side rocker arms are in rolling contact with the corresponding cams through rollers mounted on the rocker arms. The exhaust-side a rocker arms are provided with notches in the area near the cam shaft for accommodating portions of the intake-side rocker arms, respectively. Thus, it is possible to reduce the loss of valve operational friction to the utmost, to position the rocker arms in an axially compact arrangement and to position the intake valves and exhaust valves at a small angle.

Valve operating system in internal combustion engine

A valve operating device for the intake or exhaust valves of an internal combustion engine wherein a plurality of cam followers are disposed adjacent to each other for operation by different cams in mutually different modes dependent on the speed of rotation of a camshaft. A selective coupling mechanism disposed in and between the cam followers has switching pins movable between a connecting position in which the cam followers are interconnected and a disconnecting position in which the cam followers are disconnected. An oil passage is provided in one or more of the cam followers and the switching pin therein is arranged to control the rate of flow of oil through the oil passage defined in that cam follower in response to movement of the switching pin between the connecting and disconnecting positions. The oil supplied through the oil passage is used for lubricating the cam and cam following sliding surfaces in one embodiment and for operating hydraulic valve lash adjusters in another embodiment.

Valve operating device for internal combustion engine

Growing community of inventors

Saitama, Japan

Yoshihito Tsuji