摘要:
An engine-control system is structured in such a way that a timing for closing the intake valve is retarded and the air-fuel ratio is so set as to become a rich air-fuel ratio richer than, for example, the stoichiometric air-fuel ratio, in a region where the load is low. On the other hand, in a region where the load is high, the timing for closing the intake valve is set earlier and the air-fuel ratio is so set as to become a lean air-fuel ratio leaner than, for example, the stoichiometric air-fuel ratio.
摘要:
An internal combustion engine with a supercharger with a piston arranged to be inserted into a cylinder so as to move in a reciprocating way, which has a bore size of the cylinder ranging from approximately 43 mm to 67 mm; a volume of a single chamber of the cylinder ranging from approximately 110 cc to 400 cc; a ratio of a stroke of the piston to the bore size of the cylinder being larger than 1; and a compression ratio of the engine being 9 or larger.
摘要:
A supercharging apparatus for an internal combustion engine comprises an intake air passage communicating with a cylinder of an engine through an intake valve; a mechanical supercharger provided in the intake air passage; a variable valve timing mechanism for varying a closing timing of the intake valve with respect to a bottom dead center of an engine piston; a control unit for controlling the variable valve timing mechanism in accordance with an engine speed at least in a supercharging region wherein the mechanical supercharger is operative to supply supercharged air into the cylinder, in such a manner that the closing timing of the intake valve is switched between an advanced timing and a delayed timing; and an assist intake system for causing a dynamic supercharging effect in the intake air passage when the closing timing of the intake valve is switched to the delayed timing, thereby assisting the mechanical supercharger in a low engine operational region.
摘要:
A method for controlling an engine includes, when the engine is operating within a particular range with comparatively low engine speed and high load, setting an effective compression ratio of 10:1 or above, retarding ignition timing by a predetermined amount and retarding the ignition timing within a first, relatively low engine speed range more than within a second, higher engine speed range, setting an injection mode of an injection valve to divided injections performed at least twice in a period from an intake stroke to an earlier-half stage of a compression stroke, performing, within the first engine speed range, a final injection in the earlier-half stage of the compression stroke, and performing, within the second engine speed range, the final injection in a late stage of the intake stroke and at least one injection other than the final injection in a middle stage of the intake stroke.
摘要:
A spark ignition type reciprocating engine of a natural intake system with an ignition plug arranged to face a combustion chamber defined and delimited by a piston inserted into a cylinder so as to move in a reciprocating way, which has:a bore size of the cylinder ranging from approximately 45 mm to 67 mm;a volume of a single chamber of the cylinder ranging from approximately 110 cc to 340 cc;a ratio of a stroke of the piston to the bore size of the cylinder being larger than 1; anda compression ratio of the engine being 11 or larger.
摘要:
An engine has a geometric compression ratio of higher than 12, and includes an exhaust manifold, a variable exhaust valve timing mechanism, an ignition timing controller, and an effective compression ratio adjuster. The exhaust manifold has a plurality of branched exhaust passages connected to the respective exhaust ports of the individual cylinders; a plurality of first collector segments each of which joins the branched exhaust passages for the cylinders which are not adjacent in the exhaust order sequence; a plurality of middle exhaust passages connected to the downstream of the first collector segments, respectively; and a second collector segment that joins the middle exhaust passages. In at least low and middle speed ranges in a high load region of the engine, the effective compression ratio is set to have a value larger than 10 and the ignition timing is retarded, and the valve opening time of the exhaust valve is changed according to the engine speed so that a predetermined amount of a valve overlap period is ensured and that negative pressure waves from exhaust pressure pulses reach an exhaust port during the valve overlap period in a plurality of engine speed ranges. This effectively reduces knocking in low and middle speed ranges in a high load region of the engine while achieving high torque by keeping the compression ratio high.
摘要:
A controller for a supercharged engine includes a supercharger for supercharging intake air, an intercooler for cooling the intake air discharged from the supercharger, a valve timing varying device for varying valve timing so that an overlapping term, in which both intake and exhaust valves open, is longer when an engine speed is relatively high than when the engine speed is relatively low, and a controller for controlling the valve timing varying device so that when the overlapping term is short at relatively low speed of the engine, the intake valves close at a timing later than a timing at which the intake valves close when the overlapping term is long at relatively high speed of the engine.
摘要:
An engine has a torque peak in a middle engine speed range. An engine output control system reduces the engine output torque in the middle engine speed range so that the torque characteristic curve of the engine becomes flat when the vehicle is accelerated from a low engine speed range at a low gear speed.
摘要:
An engine control system for controlling an internal combustion engine equipped with a mechanical supercharger includes a valve timing control mechanism which causes first and second intake valves for each cylinder to retard opening and closing of a first intake port with respect to opening and closing of a second intake port. Opening and closing of the first intake port is retarded when a specific range of engine operating conditions, in which the supercharger is operating, is detected.
摘要:
The engine is provided with an auxiliary chamber having an auxiliary chamber port with an opening communicated with the combustion chamber. The auxiliary chamber port is arranged to be opened or closed with an auxiliary chamber valve. The timing of closing the auxiliary chamber valve is in between a final stage of compression stroke in which the temperature within the cylinder becomes higher and an initial stage of explosion stroke. On the other hand, the timing of opening the auxiliary chamber valve is in a middle stage of the compression stroke, thereby allowing the mixed fuel cooled in the auxiliary chamber to be replaced with a portion of the mixed fuel in the combustion chamber, thereby lowering the temperature within the cylinder.