Abstract: To avoid a sudden change in torque when switching over the valve lift of discretely adjustable inlet valves, the valve lift is firstly only adjusted for a section of cylinders, while the valve lift for the remaining section of cylinders is switched over after a delay. Therefore with each valve lift adjustment, only a slight change in torque has to be compensated by means of a corresponding change in the efficiency of the cylinders.

Abstract: An intake valve phase shift in multi-valve engines to enhance air-fuel mixing and optimum combustion at all operating conditions. The intake valve members are independently operated by electro-mechanical actuators or the like, and activated and deactivated by the electronic controller of the engine. A channel or passageway in a diverter member positioned between the two intake ports in the cylinder head allows air and fuel from a closed intake port to be diverted to an open intake port and thus into the combustion chamber. The passageway preferably has a configuration with a certain curvature, orientation and position relative to the diameter of the inlet ports. The curvature is about one-half the diameter D of the inlet port, the passageway is symmetrical from port to port and directs the fuel toward the opposite sides of the ports, and the passageway is positioned about D/4 from the valve seats.

Abstract: The invention relates to a multi-cylinder internal combustion engine with gas flow lift valves actuated by electromagnetic actuators and controlling the intake and the exhaust of the cylinder combustion chambers. The cross-sectional area of the actuators allocated to the intake lift valves which is perpendicular to the axial direction of the lift valves is smaller than the cross-sectional area of the actuators allocated to the exhaust lift valves. If the intake lift valves and the exhaust lift valves are arranged in series one after the other in the direction of the longitudinal axis of the internal combustion engine, the width of the intake actuators measured in the plane of the actuator cross-sectional area and perpendicular to the longitudinal axis of the internal combustion engine is smaller than that of the exhaust actuators.

Abstract: Valve clearance adjusting shims in an internal combustion engine having an overhead cam, are removed and replaced by compressing a valve spring through a cam follower forcibly held against the spring pressure by a valve clearance tool. A method for relieving pressure against the valve spring and for replacing the valve clearance adjusting shims is described.

Abstract: The present invention is directed to an actuator piston assembly for use in a rocker arm system. The actuator piston assembly is capable of actuating at least one engine valve during for example engine braking. The actuator piston assembly includes a piston body having a hollow interior, a screw assembly received within the hollow interior of the screw assembly, a biasing assembly for biasing the piston body with respect to the screw assembly, a cap assembly located within the hollow interior, wherein the biasing assembly interacts with the cap assembly and the screw assembly, and a securing assembly for movably securing the piston body to the screw assembly.

Abstract: Variable valve characteristic control apparatuses realize a change in a valve characteristic in accordance with a requirement of an internal combustion engine and a three-dimensional cam for use in the variable valve characteristic control apparatus. In the case of an intake valve, two lift patterns and continuously varying lift patterns between the two lift patterns are realized by the three-dimensional cam through the driving of the variable valve characteristic control apparatus. The two lift patterns provide different amounts of lift in the delay side of a peak within a valve operation angle, but provide equal amounts of lift in the delay side of the peak. Since the intake cam has the two lift patterns, it is possible to select a phase where the two lift patterns provide equal amounts of lift and provide different amounts of lift in phases other than the equal-lift phase so as to accord to the characteristics of the internal combustion engine.

Abstract: Variable valve characteristic control apparatuses realize a change in a valve characteristic in accordance with a requirement of an internal combustion engine and a three-dimensional cam for use in the variable valve characteristic control apparatus. In the case of an intake valve, two lift patterns and continuously varying lift patterns between the two lift patterns are realized by the three-dimensional cam through the driving of the variable valve characteristic control apparatus. The two lift patterns provide different amounts of lift in the delay side of a peak within a valve operation angle, but provide equal amounts of lift in the delay side of the peak. Since the intake cam has the two lift patterns, it is possible to select a phase where the two lift patterns provide equal amounts of lift and provide different amounts of lift in phases other than the equal-lift phase so as to accord to the characteristics of the internal combustion engine.

Abstract: Variable valve characteristic control apparatuses realize a change in a valve characteristic in accordance with a requirement of an internal combustion engine and a three-dimensional cam for use in the variable valve characteristic control apparatus. In the case of an intake valve, two lift patterns and continuously varying lift patterns between the two lift patterns are realized by the three-dimensional cam through the driving of the variable valve characteristic control apparatus. The two lift patterns provide different amounts of lift in the delay side of a peak within a valve operation angle, but provide equal amounts of lift in the delay side of the peak. Since the intake cam has the two lift patterns, it is possible to select a phase where the two lift patterns provide equal amounts of lift and provide different amounts of lift in phases other than the equal-lift phase so as to accord to the characteristics of the internal combustion engine.

Abstract: Disclosed is an overhead rocker cam valve operating device for an internal combustion engine and which is particularly useful for race cars or high performance automobiles. The device includes a rocker cam and connecting fixed plate, the rocker cam arm being adjustable within a slot in the fixed plate to provide for more or less power. Hence, the rocker cam arm can be positioned closest to the cam lobe to provide for performance or speed, or can be positioned farther from the cam lobe to provide for less power or economy.

Abstract: A drive train for a four stroke, overhead cam engine is provided, comprising a crankshaft, connecting rod, and piston assembly for reciprocating the piston within the cylinder bore of a cylinder block. An internally profiled cam gear is driven around an axis perpendicular to the axis of the cylinder block. A pair of follower arms extend from a pair of rocker arms and engage the cam profile to actuate intake and exhaust valves in the cylinder block. An intermediate gear is driven by the crankshaft at half speed to drive the cam gear, and may also be used to drive an additional device, such as a combination oil pump and governor. The cam follower arms may be disposed in an overlapping crosswise arrangement generally parallel to the cam gear, or may be disposed perpendicular to the cam gear.

Abstract: When a valve 10 is opened, a locking ball 8 moves upward with respect to a rocker arm 3 and the locking ball is located between the rocker arm 3 and a push rod 5. The push rod 5 moves downward integral with the rocker arm 3 in a condition the push rod 5 is locked. When a valve 10 is closed, the locking ball 8 moves downward with respect to the rocker arm 3 and the push rod 5 is placed in unlocked condition. A retaining member 3A in the rocker arm 3 contacts the circlip 9 and the push rod 5 moves upward. By this construction, it becomes possible to eliminate adjustment work of tappet clearances and also unfavorable conditions caused by adjustment work of tappet clearances.

Abstract: A method for evaluating the combustion chamber pressure in an internal combustion engine is described, in which the output signal of at least one cylinder pressure sensor and one crankshaft angle sensor is performed by the control unit of the engine. By analysis of the course of combustion chamber pressure over the crankshaft angle, characteristic pressure courses are obtained for certain valve control times. From these characteristic pressure courses, a conclusion can be drawn as to the valve control times “outlet opens”, “outlet closes”, “inlet opens”, and “inlet closes”, referred to the crankshaft angle.

Abstract: A rotary-to-linear converter for use with a valve actuation device having a linear reciprocating cam shaft having longitudinally extending cam grooves that are engaged by captive cam followers which oscillate up and down in response to sideways reciprocation of the camshaft for actuating intake or exhaust valves of internal combustion engines or other devices employing reciprocating pistons and valves. The camshaft is caused to reciprocate by a rotary linear converter of the “yankee” type composed of double helix channel at the extreme end of the camshaft and a rotary drive collar having two sets of diametrically opposed guide members. The guide members comprise dogs which are rotatably engaged with the drive collar and slidably engaged with the double helix channel of the cam shaft.

Abstract: A method for evaluating the combustion chamber pressure in an internal combustion engine is described, in which the output signal of at least one cylinder pressure sensor and one crankshaft angle sensor is performed by the control unit of the engine. By analysis of the course of combustion chamber pressure over the crankshaft angle, characteristic pressure courses are obtained for certain valve control times. From these characteristic pressure courses, a conclusion can be drawn as to the valve control times “outlet opens”, “outlet closes”, “inlet opens”, and “inlet closes”, referred to the crankshaft angle.

Abstract: A rocking follower mechanism for a three-dimensional cam is provided. The rocking follower mechanism prevents a hit sound without generating excessive abrasion on a cam follower or a cam surface of the three-dimensional cam, while providing a wide portion for the cam follower. The cam follower is restricted from moving in the axial direction. The wide portion of the cam follower is formed at a position so as not to be brought into contact with the cam surface of the intake cam. As a result, collision of the cam surface against an angular portion defined by a thrust surface and an end surface of the wide portion, i.e., direct abutment against the end surface, can be avoided. Therefore, it is possible to prevent the hit sound without generating excessive abrasion on the cam surface of the intake cam or the cam follower itself. Accordingly, excellent riding comfort of the vehicle can be maintained.