Abstract: An intake valve assembly of an internal combustion engine that includes a combustion chamber and an intake passage. The intake valve assembly comprises a primary valve provided to seal against a primary valve seat formed in an intake port, a secondary valve mounted about the primary valve coaxially therewith and provided to seal against a secondary valve seat formed in the intake port, and a secondary valve lifter fixed to the primary valve so as to be axially spaced from the secondary valve when both the primary and secondary valves are in closed positions. The secondary valve is operated mechanically by the secondary valve lifter and fluidly in response to pressure differential between the intake passage and the combustion chamber.

Abstract: (In a Two Stroke engine, there is very little opportunity for scavenging residual exhaust gas, without using impractical exhaust pipe tuning.) Our design utilises momentum air-filling of the cylinder. We use overhead poppet valves, but we have positioned the inlet valve at an angle, and partly recessed it. The angled upstream side of the valve head and the wall of the recess direct airflow. The eminence positioned in the inlet port augments this by a Coanda effect. Air is thus directed alongside and under the exhaust gas, to promote scavenging and optimise volumetric efficiency. This also creates a combustion chamber in the coolest part of the cylinder head, an important consideration. Complex surfaces, liable to overheat, have been avoided. The design is simple and robust.

Abstract: A split-cycle engine includes a crankshaft rotatable about a crankshaft axis. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through intake and compression strokes during a single rotation of the crankshaft. An expansion piston is slidably received within an expansion cylinder and operatively connected to the crankshaft such that the expansion piston reciprocates through expansion and exhaust strokes during a single rotation of the crankshaft. A crossover passage interconnects the expansion and compression cylinders. The crossover passage includes crossover compression (XovrC) and crossover expansion (XovrE) valves defining a pressure chamber therebetween. At least one of the XovrC and XovrE valves is a balanced valve.

Abstract: An intake valve assembly of an internal combustion engine that includes a combustion chamber and an intake passage. The intake valve assembly comprises a primary valve provided to seal against a primary valve seat formed in an intake port, a secondary valve mounted about the primary valve coaxially therewith and provided to seal against a secondary valve seat formed in the intake port, and a secondary valve lifter fixed to the primary valve so as to be axially spaced from the secondary valve when both the primary and secondary valves are in closed positions. The secondary valve is operated mechanically by the secondary valve lifter and fluidly in response to pressure differential between the intake passage and the combustion chamber.

Abstract: A method of operating an engine including at least a cylinder and a valve controlled by an electric valve actuator, said actuator including at least a coil and an armature moveable thereto, said armature coupled to said valve, the method comprising of moving the armature toward the coil by varying an amount of current supplied to the coil in response to a location of the armature relative to the coil; identifying a first level of current supplied to the coil at a first position of the armature during said moving the armature toward the coil; and holding the armature at a second position relative to the coil by supplying a holding current to the coil, wherein said holding current is adjusted to be less than said first level of current.

Abstract: One embodiment of the present invention provides a poppet valve offering an increased valve area, comprising an outer valve head having an outer valve port and an inner valve head having an inner valve port. The inner valve head is rotatable relative to the outer valve head to align the inner and outer valve ports, thereby increasing the effective valve area of the poppet valve. The path created by aligning the inner and outer valve ports can be designed to mix air flowing through the poppet valve. Another embodiment of the present invention provides a valve guide containing a poppet valve having a guide pin, wherein the guide pin rests within a groove in the valve guide. As the poppet valve moves through the valve guide, the groove controls movement of the guide pin and causes the poppet valve to rotate relative to the valve guide.

Abstract: One embodiment of the present invention provides a poppet valve offering an increased valve area, comprising an outer valve head having an outer valve port and an inner valve head having an inner valve port. The inner valve head is rotatable relative to the outer valve head to align the inner and outer valve ports, thereby increasing the effective valve area of the poppet valve. The path created by aligning the inner and outer valve ports can be designed to mix air flowing through the poppet valve. Another embodiment of the present invention provides a valve guide containing a poppet valve having a guide pin, wherein the guide pin rests within a groove in the valve guide. As the poppet valve moves through the valve guide, the groove controls movement of the guide pin and causes the poppet valve to rotate relative to the valve guide.

Abstract: A two-piece intake assembly such as a coaxial poppet valve includes a main poppet valve with a stem attached to a head and an auxiliary poppet valve movable on the inner valve. A guiding element on the outer valve is configured to receive the inner valve stem, and is connected to an outer valve head configured to mate with the inner valve head and form a seal. The assembly provides a first vent opening formed by the action of a rocker arm on the inner valve stem and a second opening formed by the pressure differential between the combustion chamber and the intake port.

Abstract: Disclosed is a simple, easy-to-produce, and reliable connection between a shaft of a gas exchange valve and an actuator. This connection is detachable and, as a result, can be connected and disconnected multiple times. It is also possible to dispose the coupling piece on the shaft of the gas exchange valve and provide circumferential grooves on the control element of the actuator.

Abstract: An internal combustion engine is provided in which an intake valve, which opens and closes an intake valve hole formed in a cylinder head facing a combustion chamber has a hollow structure. An exhaust valve hole formed in the intake valve is made to open and close by an exhaust valve coaxially housed within the intake valve. The intake valve hole communicates directly with an intake port, and the exhaust valve hole coniniunicates with an exhaust port via an exhaust passage formed within the hollow intake valve. This ensures that the intake valve has a large opening area, thus increasing the intake charging efficiency. Furthermore, since exhaust gas coming out of the combustion chamber does not make direct contact with the cylinder head, which has a large heat capacity, any decrease in temperature of the exhaust gas can be minimized, thereby utilizing waste heat effectively.

Abstract: A dual spring valve stem seal module utilizes an inner retention spring to incorporate a valve stem seal assembly, a valve spring and a spring retainer. The dual spring valve stem seal module reduces the inventory and simplifies the assembly required for the valve stem seal assembly, the valve spring and the spring retainer, thereby reducing the costs associated therewith.

Abstract: A valve train of an internal combustion engine has rocker arms which are spherically supported on lash adjusters and camshafts disposed above the rocker arms. The camshafts are rotatably supported on a cam holder including a lower cam holder which is fastened to a cylinder head and an upper cam holder. Projections for preventing the fall of the rocker arms in axial directions of the camshafts through the contact with the rocker arms are provided on bearing portions and partitioning portions which are integrally formed on the lower cam holder in such a manner as to face both sides in the axial direction of the rocker arms.

Abstract: A valve having a sleeve-like screening element for protecting an internal combustion engine against deposits in a region extending up from a hollow throat to a stripping edge. The screening element has a separate contactor guide surface for the combustion air supplied to the combustion chamber whose surface temperature is lower than the critical temperature for deposits at which fuel particles coke.

Abstract: For making an interconnection between a valve head and stem, the interconnection between these parts is made by pouring a cast alloy around the stem end. A connection and a valve are also provided.

Abstract: A self-cleaning valve for removing hydrocarbon deposits from pressure responsive automatic air intake valves in an internal combustion engine. The self-cleaning valve assembly of the present invention removes soot which naturally accumulates on the surface of the valve as a result of the heat generated by the combustion event when hydrocarbon fuel sources are used. A reciprocating slider is seated within a bushing. The bushing is fluted with small relief passages along its length. The fluted relief passages run more or less parallel to the direction of the movement of the slider, and provide channels for removing soot from the surface of the valve. Repeated closing of the slider hammers soot upwardly into the relief passages, thereby maintaining the valve free of potentially fouling hydrocarbon deposits.

Abstract: A valve train of an internal combustion engine has rocker arms which are spherically supported on lash adjusters and camshafts disposed above the rocker arms. The camshafts are rotatably supported on a cam holder including a lower cam holder which is fastened to a cylinder head and an upper cam holder. Projections for preventing the fall of the rocker arms in axial directions of the camshafts through the contact with the rocker arms are provided on bearing portions and partitioning portions which are integrally formed on the lower cam holder in such a manner as to face both sides in the axial direction of the rocker arms.

Abstract: In a composite lightweight valve for internal combustion engines having a solid valve head provided with a center opening and a valve stem received in the center opening of the valve head in a positively locking manner, the valve components are permanently joined to one another by hot upsetting so as to be capable of withstanding the thermal and mechanical effective during engine operation.

Abstract: The present invention provides an apparatus and method for selective control of gas flow in a combustion chamber in an internal combustion engine through a moveable or retractable seat valve that is independent of piston position. The retractable seat valve has complete freedom of valving events such that gas flow can be selectively controlled at any time during the engine cycle, or throughout the engine cycle. Further, the retractable seat valve is scalable for adaptation to internal combustions engines of various bore sizes. The retractable seat valve includes a retractable seat, a stationary seat, a retractable seat actuator member, a pin connector for translation of retractable seat actuator member movement to the retractable seat, and a valve actuator assembly that allows the retractable seat valve be selectively positioned in the cylinder head in a closed position, open position or anywhere therebetween.

Abstract: A method of manufacturing surface treated, prefinished valve seat inserts. The method entails forming the valve seat insert, precision machining the valve seat insert to precise tolerances so that the valve seat insert can be installed in one of the cylinder head and engine block without the need for additional seat machining and treating the valve seat insert with a wear resistant treatment prior to inserting the valve seat insert into on of the cylinder head and engine block.

Abstract: A valve spring retainer is fixed at the upper end of a poppet valve via a pair of cotters in a valve-operating mechanism of an internal combustion engine. The valve spring retainer comprises a hollow inverted-frustoconical portion and an outward flange at the end thereof. The lower surface of the outward flange retains the upper end of a valve spring on the lower surface. An annular projection is provided on the outward flange to restrict sideward movement of the valve spring and to increase rigidity of the retainer.

Abstract: A valve having a sleeve-like screening element for protecting an internal combustion engine against deposits in a region extending up from a hollow throat to a stripping edge. The screening element has a separate contactor guide surface for the combustion air supplied to the combustion chamber whose surface temperature is lower than the critical temperature for deposits at which fuel particles coke.

Abstract: An exhaust valve for an internal combustion engine including a movable spindle with a valve disc which on its upper surface has an annular seat are of a material different from the base material of the valve disc. In the closed position of the valve the seat area abuts a corresponding seat area on a stationary valve member. The seat area on the upper surface of the valve disc is made of a material which has a yield strength of at least 1000 Mpa at a temperature of approximately 20° C.

Abstract: A hollow poppet valve (31) is disclosed, in which a stem portion (13) includes a flared fillet portion (17), having a wall thickness (T), and a downwardly-extending cylindrical portion (33;51), having a cylindrical external surface (35). In the main embodiment, the valve includes a cap member (15) defining a seat face (25), and a cylindrical internal surface (39), the internal and external surfaces (39,35) being closely spaced apart, defining an interface having an axial length (L), and being consumed by a weld (43). Preferably, the length (L) of the weld (43) is equal to at least 1.1 times the thickness (T). The fillet portion (17) defines an internal fillet radius (R1), greater than 0.3 times the thickness (T), and near the radius (R1) is a transition region (TR). The present invention improves fatigue strength of the poppet valve by separating the transition region (TR) from the weld (43) so that there is overlap for no more than a minor portion of the weld.

Abstract: An exhaust valve for an internal combustion engine including a movable spindle with a valve disc of a nickel-based alloy which also constitutes an annular seat area at the upper surface of the valve disc. The seat area abuts a corresponding seat area on a stationary valve member in the closed position of the valve. At manufacturing, the seat area of the valve disc is subjected to a thermo-mechanical deformation process at a temperature lower than or around the recrystallization temperature of the alloy. The seat area on the upper surface of the valve disc has been given dent mark preventing properties in the form of a yield strength of at least 1000 MPa at a temperature of approximately 20° C. by means of the thermo-mechanical deformation process and possibly a yield strength increasing heat treatment.

Abstract: A two piece intake valve for internal combustion engines comprising an inner and an outer valve which can be designed with orbicular heads. The inner valve including a stem of a smaller outer diameter than the outer valve. The outer valve including a hollow stem large enough to accept the inner valve stem, an inner valve guide, and an inner valve control spring and retainer mechanism. The outer valve also including a valve seat in the center of its bottom face to seat the inner valve. The head, or base, being equipped with one or more vents which communicate between the intake port and the combustion chamber and being releasably opened and sealed off by the inner valve. The vented valve unit incorporating an independent actuation means by way of pressure differentials created by the induction cycle, and/or directional inertia factors of the mechanically controlled valve element. The vented valve unit also incorporating design features to effectively control and dampen inner valve closing.

Abstract: A shrouded engine valve having a shroud wall so as to direct and swirl a mixture of fuel and air into a combustion chamber of an internal combustion engine. The arrangement of the invention improves the efficiency of combustion and thereby engine performance. The shrouded engine valve may be manufactured as a single unit, or with a multiple piece design.