A valve train system that eliminates the inefficiencies of current spring biased systems. The system uses teeter beams that are manipulated by cams that are driven by cam shafts to control and operate the valve system more efficiently and dependably.

The control apparatus operates an engine water temperature adjustment apparatus so that the temperature of cooling water that passes through an engine head enters a first temperature region in a lean mode, and operates the engine water temperature adjustment apparatus so that the temperature of the cooling water enters a second temperature region that is lower than the first temperature region in a stoichiometric mode. When knocking is detected after switching is started from the stoichiometric mode to the lean mode, the control apparatus performs any one of a first operation to operate a variable valve apparatus so as to retard the closing timing of an intake valve, a second operation to operate an oil jet apparatus so as to increase an oil jet amount, and a third operation to operate an EGR apparatus so as to increase an EGR amount.

A two-stroke, opposed-piston engine includes a cylinder with an inlet piston controlled inlet port and an exhaust piston controlled exhaust port, the cylinder defining a combustion chamber with the inlet piston and the exhaust piston, a charge air channel in flow communication with the inlet port, a conduit extending directly from the combustion chamber to the charge air channel, and a valve arranged to selectively open and close flow communication through the conduit.

An engine power unit includes a crankcase, a cylinder body, and a cylinder head sequentially stacked and fastened with each other. A cam shaft holder is fastened to the cylinder head to rotatably support a cam shaft of an engine valve operating mechanism. A cylinder head cover covers the cylinder head and the cam shaft holder. Fastening bolts penetrate the cylinder head cover and the cam shaft holder to be screwed into the cylinder head. Pressing surfaces are formed on the inner surface of the cylinder head cover. The pressing surfaces are abutted against and press the cam shaft holder to the cylinder head. Thus, rigidity around the cylinder head is enhanced, and a weight reduction of the power unit is achieved.

A multiple variable valve lift apparatus may include a camshaft rotating by driving of an engine, a cam portion formed in a cylindrical shape having a hollow that the camshaft is inserted into, rotating together with the camshaft, configured to move along an axial direction of the camshaft, and forming a zero cam and a normal cam, a valve opening/closing device configured to be operated by at least one of the zero cam or the normal cam which are formed at the cam portion, an operating device disposed on an exterior circumference of the camshaft so as to move together with the cam portion, and a solenoid configured to selectively move the operating device along an axial direction of the camshaft, in which a journal, which has a radius being equal to a radius of the zero cam, is formed at the cam portion.

A multiple variable valve lift apparatus may include a camshaft rotating by driving of an engine, a cam portion formed in a cylindrical shape having a hollow that the camshaft is inserted into, rotating together with the camshaft, configured to move along an axial direction of the camshaft, and forming a zero cam and a normal cam, a valve opening/closing device configured to be operated by at least one of the zero cam or the normal cam which are formed at the cam portion, an operating device disposed on an exterior circumference of the camshaft so as to move together with the cam portion, and a solenoid configured to selectively move the operating device along an axial direction of the camshaft, in which a journal, which has a radius being equal to a radius of the zero cam, is formed at the cam portion.

A rocker arm assembly operable in an engine drive mode and at least one of a late intake valve closing (LIVC) mode and an internal exhaust gas recirculation (iEGR) mode, the rocker arm assembly selectively opening first and second engine valves. The rocker arm assembly includes a rocker arm configured to rotate about a rocker shaft, and a reverse reset capsule assembly movable between (i) a locked position configured to perform one of an LIVC operation and an iEGR operation, and (ii) an unlocked position that does not perform the LIVC operation or the iEGR operation. An actuator assembly is configured to selectively move the reverse reset capsule assembly between the first and second positions.

A beam-like crosshead for a valve train of an internal combustion engine is proposed for the transmission of a cam lift to two gas exchange valves. The crosshead has two side walls which are connected by a transverse wall, and, on an upper side of the transverse wall at its longitudinal center, a contact surface for a cam follower, and, on an underside of the transverse wall at each of its longitudinal ends, a valve contact surface. The crosshead is a reversed bowl-like hollow body which is produced from steel sheet using stamping/bending technology. From the transverse wall the side walls and, transversely at each longitudinal end, end walls hang in a finger-like manner. Cut edges between the side and end walls, starting from the transverse wall, form cut-outs.

In an internal combustion engine, first and second rotating members, one for the intake valve and one for the exhaust valve rotate next to the outside of an engine cylinder on opposite sides thereof when driven by a drive gear attached to the end of the engine's crankshaft. Each rotating member may include a ring gear having a valve port or aperture near its perimeter that cyclically aligns with a corresponding valve port formed through the cylinder wall near the top of the cylinder. A method of controlling valve timing comprises the steps of causing the rotating member containing the second valve port to periodically align in synchronism with the first port to control the passage of an air/fuel mixture and exhaust gases through the combustion cycles of the engine.

In an internal combustion engine, first and second rotating members, one for the intake valve and one for the exhaust valve rotate next to the outside of an engine cylinder on opposite sides thereof when driven by a drive gear attached to the end of the engine's crankshaft. Each rotating member may include a ring gear having a valve port or aperture near its perimeter that cyclically aligns with a corresponding valve port formed through the cylinder wall near the top of the cylinder. A method of controlling valve timing comprises the steps of causing the rotating member containing the second valve port to periodically align in synchronism with the first port to control the passage of an air/fuel mixture and exhaust gases through the combustion cycles of the engine.