Honda Giken Kogyo Kabushiki Kaisha

Masaaki Katoh

Kazuo Inoue

Kenichi Nagahiro

Yoshio Ajiki

Noriyuki Kishi

A valve operation mode changing system for the intake or exhaust valves of an internal combustion engine is controlled in response to engine speed and temperature of the working oil utilized in the system in such a way as to permit the valve operating mode to be changed from a low-speed to a high-speed mode in response to engine speed requirements only when the temperature of the working oil exceeds a predetermined value. The system also provides for terminating fuel supply to the engine when the temperature of the working oil is below a predetermined temperature and the speed of the engine exceeds a predetermined temperature.

Valve operating device for internal combustion engine

Valve operating apparatus is disclosed in which intake or exhaust valves for an internal combustion engine are operated by rocker arms driven by cams and have a hydraulically operated coupling mechanism for selectively connecting or disconnecting adjacent rocker arms to vary the operation timing of the valves under different engine operating conditions. The fluid circuit for operating the coupling mechanism contains a valve which is energized to a closed position during low-speed engine operation and de-energized to an open position during high-speed engine operation.

Apparatus for changing operation timing of valves for internal

A valve operating mechanism for operating a plurality of valves of a particular cylinder of an internal combustion engine includes a camshaft rotatable in synchronism with rotation of the internal combustion engine and having at least one cam. At least one of a plurality of cam followers slidably engages the cam for selectively operating the valves according to a cam profile of the cam. The cam followers are selectively interconnected and disconnected to operate the valves in different speed ranges of the internal combustion engine, the speed ranges including a range in which all of the valves remain inoperative. The camshaft has one or two annular raised portions in addition to the cam, and the cam followers include one or two cam followers which slidably engage the raised portion or portions. The valves remain inoperative by the annular portion or portions and are operated in a high-speed range by the cam, or selectively in low- and high-speed ranges by low- and high-speed ranges.

Valve operating mechanism for internal combustion engine

A valve operating mechanism for operating a single valve of a particular cylinder of an internal combustion engine includes a camshaft rotatable in synchronism with rotation of the internal combustion engine and having at least one cam, and a plurality of cam followers, one of which slidably engages the cam for selectively operating the valves according to a cam profile of the cam. The cam followers are selectively interconnected and disconnected to operate the valve differently in different speed ranges of the internal combustion engine. In different embodiments, the camshaft has an annular raised portion and low- and high-speed cams, or low-, medium-, and high-speed cams, or an annular raised portion and a cam, and the cam followers are held in sliding contact with these raised portion and cams. The valve is selectively kept inoperative by the raised portion and operated in low- and high-speed ranges by the low- and high-speed cams, or selectively operated in low-, medium-, and high-speed ranges by the low-, medium-, and high-speed cams, or selectively kept inoperative by the raised portion and operated in a high-speed range by the cam.

A valve operating mechanism for operating a plurality of valves of an internal combustion engine includes a camshaft rotatable in synchronism with rotation of the internal combustion engine and having an array of three cams including a high-speed cam positioned at one end of the array. Three cam followers are held in sliding contact with the cams, respectively, for operating the valves according to cam profiles of the cams. The cam followers are selectively interconnected and disconnected to operate the valves at different valve timings in different speed ranges of the internal combustion engine. The speed ranges include a high-speed range in which all of the valves are controlled by the cam profile of the high-speed cam. The three cams may include low- and medium-speed cams, or two identical or different low-speed cams, in addition to the high-speed cam. These cams may be differently arranged in the array, and the cam followers include those which slidably engage one or two of the cams for operating the valves. The valves are operated selectively in low- and high-speed ranges, or in low-, medium-, and high-speed ranges, with different combinations of the cams.

A valve operating mechanism for operating at least one valve of an internal combustion engine, includes a camshaft rotatable in synchronism with rotation of the internal combustion engine and having a pair of low- and high-speed cams of different cam profiles, a rocker shaft, and a pair of first and second rocker arms rotatably mounted on the rocker shaft and operable selectively by the low- and high-speed cams for operating the valve according to the cam profiles of the cams. A selective coupling is operatively disposed in and between the first and second rocker arms for interconnecting the first and second rocker arms in high-speed operation of the engine and for disconnecting the first and second rocker arms from each other in low-speed operation of the engine.

A valve operating mechanism includes a camshaft rotatable in synchronism with rotation of an internal combustion engine and having a plurality of cams of different cam profiles. First, second, and third rocker arms are held in sliding contact with the cams, respectively, for operating the valves according to the cam profiles of the cams. The rocker arms are selectively interconnected and disconnected by first and second selective couplings to operate the valves at different valve timings in low, medium, and high speed ranges of the internal combustion engine.

A valve operating mechanism for operating a pair of valves of an internal combustion engine, includes a camshaft rotatable in synchronism with rotation of the internal combustion engine and having a first low-speed cam, a second low-speed cam, and a high-speed cam which have different cam profiles, respectively, the first and second low-speed cams being disposed one on each side of the high-speed cam, a rocker shaft, and first, second, and third rocker arms rotatably mounted on the rocker shaft and held in sliding contact with the first low-speed cam, the second low-speed cam, and the high-speed cam, respectively, for operating the valves according to the cam profiles of the cams. A selective coupling is operatively disposed in and between the first, second, and third rocker arms for selectively interconnecting the first, second, and third rocker arms to allow angular movement thereof in unison and disconnecting the first, second, and third rocker arms to allow separate angular movement thereof.

Growing community of inventors

Saitama, Japan

Masaaki Katoh