Abstract:
To achieve further reduction in size and weight of a cylinder head in a four-cycle engine having a connection surface formed on the cylinder head to connect a head cover set so as to follow along a plane that is inclined so as to be spaced further away from a cylinder block toward a first side wall. A camshaft holder is integrally formed on a cylinder head so as to protrude from a connection surface as viewed from an axial direction of a camshaft. An intake port is disposed in the first side wall such that an upstream end thereof is disposed at the same position as part of the bearing portion in a direction along an axis of a cylinder bore. An exhaust valve has a stem end disposed at a position protruding from the connection surface as viewed in a direction along the axial direction of a camshaft.
Abstract:
A valve train is disclosed for an internal combustion engine having a block, a camshaft in the block, and at least two push rods actuated by the camshaft. The valve train comprises first and second rockers, and three valves. The first rocker is actuated by one of the push rods, and the second rocker is actuated by another of the push rods. A first valve is associated with a cylinder of the engine and actuated by the first rocker. A second valve is associated with the cylinder and actuated by the first rocker, and a third valve is associated with the cylinder and actuated by the second rocker.
Abstract:
A multi-valve internal combustion engine having a plurality of valves having skewed axes that are operated by cam lobes of a single cam shaft. The cam shaft operates the valves through rocker arms each of which are pivoted independently about axes that are skewed relative to the cam shaft axis so as to minimize bending stresses on the valve during its actuation. This also avoids scuffing between the rocker and the valve stem. At the same time, good contact is maintained between the cam lobe and the follower surface by machining the cam lobe so that it will have a slight concavity at least in its tip portion so as to ensure constant line contact with the follower.
Abstract:
A tappet assembly for use with a valve train mechanism of an internal combustion engine that has angulated intake and exhaust valves actuated by the lobes of a pair of camshafts characterized in that the lobe of each camshaft serves to move the associated valve through an inverted bucket tappet incorporating a cylindrical force transmitting element which includes a surface that is skewed or inclined with respect to the bottom of the body of the tappet.
Abstract:
A valve train for internal combustion engines utilizing an inverted bucket tappet with a pivot structure operatively disposed between the tappet and the end of the valve stem allowing the valves to be angulated with respect to each other and to the axis of the cylinder in both the transversal and the horizontal planes of the engine. Accordingly on a multi-valve engine, the valves extend radially from the associated combustion chamber to open and increase space in the center of the cylinder head for spark plugs, injectors, or pre-combustion chambers and so that the combustion chamber can be designed with a hemispherical surface, with tangentially disposed valve heads. The construction allows the use of large valves in conjunction with stronger, better-cooled valve seats and bridges. The tappets can be actuated conventionally by direct-acting overhead camshafts or by rocker arms and "T" bridges.
Abstract:
A valve train mechanism for an internal combustion engine that includes angulated intake valves and exhaust valves extending from a curved upper wall of the combustion chamber and having a cross member provided with a roller and groove arrangement for directly actuating inverted bucket tappets associated with the intake and exhaust valves.
Abstract:
The invention has for purpose to provide a simple and light device for actuating, with equal, and even zero, operating clearances, two valves having a rod associated with a single rocker. This device comprises a rocker (1) which is pivotally mounted on a shaft (2) and includes two arms (19, 20) terminating in bosses (21, 22) respectively bearing against the end (25, 26) of associated valve rods. The rocker (1) is slidably mounted on its shaft (2) and, in the region of each boss, one of the contacting surfaces of the boss or the end of the rod is curved in the shape of a substantially spherical dome, the other surface being planar or cylindrical, the two planar or cylindrical surfaces being inclined and disposed roughly symmetrically relative to a plane (P--P) perpendicular to the shaft of the rocker.
Abstract:
An internal combustion engine optimizing small-size arrangement of the valve drive mechanism, considering that the exhaust valve diameter is smaller than the intake valve diameter.Intake and exhaust valves are in a radial arrangement, intake and exhaust cam surfaces are inclined relative to intake and exhaust cam axes, intake and exhaust rocker arm support members are inclined correspondingly in the same way and disposed between an intake camshaft and an exhaust camshaft. Pivotal support base portions of intake rocker arms and pivotal support base portions of exhaust rocker arms are disposed such that the distances thereof from a joining surface joining a cylinder head and a cylinder body are different.