摘要:
In a variable valve gear for an internal combustion engine provided with a camshaft phase change mechanism for variably controlling opening and closing timings of an intake valve, the camshaft phase change mechanism and a variable valve lift mechanism are controlled so that the closing timing of the intake valve is advanced beyond a predetermined range T1 including a bottom dead center when a load L of the internal combustion engine is less than a first predetermined value L1 and that the closing timing of the intake valve is delayed beyond the predetermined range T1 when the load L of the internal combustion engine is not less than the first predetermined value L1.
摘要:
This invention relates to an in-cylinder injection internal combustion engine. A lower wall of a cylinder head, said lower wall defining an upper wall of a combustion chamber, is configured in the form of a pentroof composed of an intake-valve-side, tilted, lower wall and an exhaust-valve-side, tilted, lower wall. A spark plug is arranged in the vicinity of a top part of the pentroof-shaped upper wall of the combustion chamber. A top wall of a piston, said top wall forming a lower wall of the combustion chamber, is configured in the form of a pentroof having an intake-valve-side, tilted, top wall and an exhaust-valve-side, tilted, top wall formed so that they correspond the intake-valve-side, tilted, lower wall and the exhaust-valve-side, tilted, lower wall of the cylinder head. A recessed portion is arranged in the intake-valve-side, tilted, top wall in the top wall of the piston.
摘要:
An intake system construction according to the present invention for an internal combustion engine is provided with a combustion chamber formed with upper and lower extremities thereof defined by a cylinder head and a piston, an intake open end arranged for being opened or closed by an intake valve, an exhaust open end arranged for being opened or closed by an exhaust valve, an intake port formed extending upwardly from the intake open end so that a vertical swirl of inducted air is formed in the combustion chamber, and an exhaust port for discharging combustion gas from the combustion chamber. The intake port is formed wider in one of halves thereof located adjacent a reference plane, which contains a central axis of a cylinder, than in the other half thereof located remote from the reference plane. The intake port is provided at a lower extremity thereof in the one half thereof with a raised portion for guiding an inducted air flow in the intake port toward an inner peripheral surface of a side wall of the cylinder.
摘要:
A cylinder head for an in-cylinder injection spark-ignition type internal combustion engine is formed with an injection passage for providing communication between a fuel injection valve and a combustion chamber. The injection passage includes a first and second passage sections disposed on the fuel injection valve side and on the combustion chamber side. The first passage section is formed, for example, into a truncated cone shape or a right circular cylindrical shape so that the cross sectional area decreases toward the fuel injection valve side or the area is constant over its entire length. The second passage section is formed to have the cross sectional area which increases toward the combustion chamber side. The fuel injected from the fuel injection valve flows into the combustion chamber via the injection passage having a gradually increasing cross sectional area, so that turbulence of fuel spray due to sudden divergent flow does not occur, resulting in an improved fuel combustion efficiency. Also, a seal seating face is formed on the inner face of the first passage section. By using a seal jig having a shape complementary to the seal seating face, a pressure leak test of cylinder head and a fuel leak test of fuel system can be achieved reliably and easily.
摘要:
An internal combustion engine includes a cylinder head having a pair of upright intake ports formed therein on opposite sides of a plug hole extending along a cylinder axis, and each intake port has an upstream-side upright part extending from the top face of the cylinder head along the cylinder axis and a downstream-side slanting part having an intake opening communicating with a combustion chamber on one side of an imaginary plane containing the cylinder axis. An upper opening of each intake port opening in the top face of the cylinder head has a peripheral edge extending along the peripheral edge of an upper opening of the plug hole, and the peripheral edge of the upstream-side upright part extends along the outer surface of a lash adjuster. When viewed in vertical section along the imaginary plane, the upstream-side upright part extends obliquely downward from the top face of the cylinder head in a direction away from the lash adjuster, and the downstream-side slanting part approaches the plug hole with decrease in distance to the combustion chamber and then extends parallel to the plug hole. The downstream-side slanting part, when viewed in vertical section perpendicular to the imaginary plane, extends away from the cylinder axis with decrease in distance to the intake opening. With the intake ports having the above overall shape and sectional shape, each intake port can be given a required cross-sectional area without increasing the dimensions of the engine, and makes it possible to form a proper intake air flow inside the combustion chamber.
摘要:
An intake system construction for an internal combustion engine includes a combustion chamber formed with upper and lower extremities thereof defined by a lower wall of a cylinder head and a top wall of a piston, an intake open end formed in the lower wall in opposition to the combustion chamber on one side of a reference plane which contains a central axis of the cylinder, an intake port formed in communication with the combustion chamber via the intake open end and extending upwardly from the intake open end so that a vertical swirl of inducted air is formed in the combustion chamber, an intake valve having a head portion for opening or closing the intake open end and a stem portion extending from the head portion to an upstream side of the intake port through the cylinder head, and a straightening member arranged in the intake port on a downstream side of the stem portion so that an inducted air flow is straightened on the downstream side of the stem portion.
摘要:
An intake system construction according to the present invention for an internal combustion engine is provided with a combustion chamber formed with upper and lower extremities thereof defined by a cylinder head and a piston, an intake open end arranged for being opened or closed by an intake valve, an exhaust open end arranged for being opened or closed by an exhaust valve, an intake port formed extending upwardly from the intake open end so that a vertical swirl of inducted air is formed in the combustion chamber, and an exhaust port for discharging combustion gas from the combustion chamber. The intake port is formed wider in one of halves thereof located adjacent a reference plane, which contains a central axis of a cylinder, than in the other half thereof located remote from the reference plane. The intake port is provided at a lower extremity thereof in the one half thereof with a raised portion for guiding an inducted air flow in the intake port toward an inner peripheral surface of a side wall of the cylinder.
摘要:
An internal combustion engine of the present invention comprises at least first and second cylinder banks each including a plurality of cylinders or a single cylinder, a first valve operating mechanism provided for each of the cylinders of the first cylinder bank for operating an intake valve or an exhaust valve of the cylinder to open and close, and a second valve operating mechanism having a valve operating characteristic different from that of the first valve operating mechanism and provided for each of the cylinders of the second cylinder bank for operating an intake valve or an exhaust valve of the cylinder to open and close.
摘要:
A method for producing synthetic gas with which a virtually soot-free synthetic gas having a good composition can be efficiently obtained by a simple device using a liquid biofuel as the starting material, and it is thereby possible to produce a high-quality liquid fuel such as methanol, gasoline or kerosene. Steam and a liquid biofuel produced by pyrolysis of a biomass are fed to the gasification space inside a reactor tube that is not loaded with a catalyst inside the reactor tube and heated to 800 to 1,200° C. from the outside via the reactor tube walls to induce an endothermic reaction and thereby a steam reforming chemical reaction between the steam and the liquid biofuel. By setting the molar ratio of the fed steam and carbon in the liquid biofuel ([H2O]/[C]) at 0.3 or higher, a synthetic gas having a good composition that is virtually free of tar and soot and is primarily H2 and CO is obtained.