Honda Giken Kogyo Kabushiki Kaisha

Takatoshi Aoki

Yoshihiro Fujiyoshi

Yasuhiro Urata

Takeshi Iwata

Koichi Fukuo

Chihaya Sugimoto

Kazutoshi Nishizawa

Toru Yagi

Hidenobu Nagase

Michio Kawamoto

Kaoru Horie

Ryuji Matsukado

Valve operating apparatus in internal combustion engine

In an internal combustion engine comprising a valve operating system connected to a pair of intake valves and arranged to open one of the intake valves only in a very small amount such that the one intake valve is brought into its substantially inoperative state, in a suction stroke mainly in a low speed rotation region of the engine, a fuel injection valve capable of injecting fuel toward a pair of intake ports independently corresponding to the intake valves, and a control means for controlling the operation of the fuel injection valve, the control means is arranged to control the fuel injection valve with a fuel injection completion time determined within a suction stroke, when the one intake valve is in the substantially inoperative state. This ensures that when the one intake valves has been brought into its substantially inoperative state, the injection of fuel by the fuel injection valve can be completed in the suction stroke, so that the injected fuel can be sequentially introduced into a combustion chamber in a condition of the other intake valve being open, thereby achieving an axially stratified air charge to provide an improved combustibility.

Internal combustion engine

An SOHC type internal combustion engine comprises a pair of intake valves and a pair of exhaust valves, which are carried in a cylinder head, for opening and closing operation, at a small angle formed by axes of both the pairs of the valves in a projected view on a plane perpendicular to a crankshaft axis including an axis of a cylinder, a single cam shaft rotatably disposed above a combustion chamber, a single rocker shaft fixedly disposed above the combustion chamber, a plurality of intake rocker arms interposed between the cam shaft and the pair of intake valves and swingably carried on the rocker shaft, a pair of exhaust rocker arms interposed between the rocker shaft and the pair of exhaust valves and swingably carried on the rocker shaft, and a plug insertion cylindrical portion which is provided in the cylinder head between both the exhaust valves and into which is inserted a spark plug disposed at a substantially central portion of a ceiling surface of the combustion chamber. In this SOHC type internal combustion engine, a connection changeover mechanism is provided in the plurality of intake rocker arms for changing over the connection and disconnection of adjacent ones of the intake rocker arms to change the operation mode of the intake valves in accordance with the operational condition of the engine.

SOHC type internal combustion engine

A SOHC type internal combustion engine includes a pair of intake valves and a pair of exhaust valves. The intake valve driving means comprises a plurality of rocker arms disposed adjacent one another, including a pair of driving rocker arms operatively connected separately to the intake valves and a connection switchover mechanism capable of switching-over the connection and disconnection of the adjacent rocker arms in accordance with the operational condition of the engine. The exhaust valve driving means comprises a pair of exhaust valve-side rocker arms operatively connected separately to the exhaust valves and disposed on opposite sides of the intake valve driving means in positions opposed to said cam shaft, respectively. In the intake valve driving means, the opening and closing mode of the intake valves can be changed in accordance with the operational condition of the engine by operation of the connection switchover mechanism, thereby providing an improvement in output from the engine. The intake valve driving means is constructed compactly by disposition of the plurality of rocker arms constituting the intake valve driving means adjacent one another in the positions opposed to the cam shaft, thereby enabling an effective and compact construction of the connection switchover mechanism provided in the intake valve driving means.

A valve-operating system for an internal combustion engine, which system includes a valve-driving piston slidably received in a cylinder body and operatively connected at one end of the piston to an engine valve spring-biased in a closing direction. A check valve and an orifice are interposed between a hydraulic pressure generating means for generating an oil pressure for causing opening of the engine valve and a damper chamber defined between the cylinder body and the valve-driving piston. The check valve permits only the flow of working oil from the hydraulic pressure generating means to the damper chamber. The orifice restricts the return of working oil from the damper chamber to the hydraulic pressure generating means. The orifice is made sufficiently short relative to its width to reduce the influence due to viscosity variations of the working oil to an extremely small level.

Valve operating system for internal combustion engine

A valve operating device for an internal combustion engine that includes a valve piston having one end facing into a damper chamber and the other end operatively coupled to an intake or exhaust valve which is spring-biased in a closing direction. A cam piston has one end operatively coupled to a cam drivable by a crankshaft and the other end disposed in a working oil chamber. A restriction mechanism uniformly restricts oil flow during final valve closing operation of the intake or exhaust valve until the valve is fully closed. The working oil chamber and damper chamber are held in communication with each other through the restriction mechanism. A bypass passage interconnects the damper chamber and the working oil chamber in bypassing relation to the restriction mechanism. A variable restriction mechanism is provided in the bypass passage capable of varying the area for oil flow according to valve closing characteristics required by the viscosity of working oil and operating conditions of the engine.

Valve operating device for internal combustion engine

A method and apparatus for controlling valve operation in an internal combustion engine having a crankshaft during with a cam for opening and closing an intake or exhaust valve which is spring-biased in a closing direction. The method comprises the steps of varying the angular phase of the crankshaft and the camshaft to control the timing of the opening of the valve and releasing the force applied by the cam to open the valve while it is being opened to control the timing of the closing of the intake or exhaust valve. The apparatus includes a phase control mechanism disposed between the crankshaft and the camshaft and a lift control mechanism disposed between the cam and the intake or exhaust valve. Both mechanisms are hydraulically operated and controlled in response to engine operating conditions.

Method of and apparatus for controlling valve operation in an internal

A valve timing control device includes a rotatable shaft, a housing including a timing wheel axially immovable but angularly movable with respect to the timing wheel, a piston disposed coaxially with the rotatable shaft and the timing wheel, a hydraulic chamber for applying a hydraulic pressure to move the piston axially, a servovalve disposed between the hydraulic pressure chamber and hydraulic pressure supply and release passages and comprising a sleeve and a spool, an actuator for axially moving the spool, and a phase adjusting mechanism operatively coupling the piston, the housing, and the rotatable shaft for varying angular relationship between the timing wheel and the rotatable shaft in response to axial movement of the piston. The actuator may be a hydraulic actuator or an electric actuator. The phase adjusting mechanism may comprise roller pins mounted on the piston and rollingly fitted in a guide groove defined in the rotatable shaft and a guide slot defined in the housing, or meshing helical teeth on the piston, the housing, and the rotatable shaft.

Growing community of inventors

Saitama, Japan

Takatoshi Aoki