Provided is a variable valve device that is for an internal combustion engine and that can increase engine performance by enabling a large amount of maximum valve lift of an air intake valve while suppressing an excessive amount of lost motion of a lost motion mechanism. The present invention is provided with: air intake-/exhaust-side swing arms (6, 64) that cause the opening/closing motion of air intake valves (3a, 3b) and air exhaust valves (61a, 61b) for cylinders #1 and #2; an air intake-/exhaust-side hydraulic lash adjuster (10a, 10b, 65a, 65b) that comprises the fulcrum of reciprocation of the swing arms; a variable mechanism that continuously varies the amount of valve lift of each air intake valve; and a lost motion mechanism (11) that causes the air intake-/exhaust-side hydraulic lash adjuster at the #1 cylinder side to halt the opening/closing motion of the air intake/exhaust valves by means of lost motion. The maximum valve lift amount of each air intake valve is controlled in a manner so as to be greater than the valve lift amount of the air exhaust valves, and the minimum valve lift amount of each air intake valve is controlled in a manner so as to be less than the valve lift amount of the air exhaust valves.

Variable valve device for internal combustion engine

Methods and systems are provided for restarting an engine in response to a driver's change-of-mind. In one embodiment, the engine is shutdown during an idle stop with the transmission in a higher gear or with the transmission tied-up to a transmission case. In response to a driver change-of-mind restart request, the transmission is downshifted, or released from the tie-up, to return driveline torque.

Method and system for engine control

It is an object to increase the reliability and durability by minimizing mixing/entry of foreign matter (contaminants) into a speed reducer. The speed reducer is provided for reducing rotation of an actuator of a variable compression ratio mechanism and for transmitting the reduced rotation to a control shaft of the variable compression ratio mechanism. The actuator and the speed reducer are attached to a sidewall of an engine main body with a housing therebetween. An oil filter, which removes contaminants from within lubricating oil, is attached to the housing with an oil-passage-forming body therebetween. A portion of the lubricating oil supplied from the oil filter immediately after having been filter-purified is supplied via a bypass oil passage, formed in the oil-passage-forming body and the housing, into a speed-reducer accommodation chamber of the housing.

Variable compression ratio internal combustion engine

Provided is a control device for an internal-combustion engine provided with a throttle valve installed in an intake path. A full intake air amount, which is the intake air amount corresponding to when the throttle valve is fully open, is calculated in accordance with engine revolution speed, and a theoretical intake air amount, which corresponds to when engine exhaust gas does not recirculate to a combustion chamber, is calculated in accordance with the full intake air amount and an intake pressure. An actual intake air amount of the engine is detected or estimated, and an exhaust gas recirculation rate is calculated using the theoretical intake air amount and the actual intake air amount. The engine is controlled using the calculated exhaust gas recirculation rate.

Control device for internal combustion engine

A variable valve device includes a camshaft which is rotatably provided in an internal combustion engine while having a cam, a rocker shaft which is arranged next to the camshaft, a valve which is driven by the cam, a cam follower rocker which is rotatably provided in the rocker shaft, and is rocked by following the cam, a valve drive rocker which is rotatably provided in the rocker shaft next to the cam follower rocker, and drives the valve, and a switching portion which be able to switch the valve drive rocker between a drive state and a non-drive state. Either a body of the cam follower rocker or a body of the valve drive rocker is made of an iron-based metal material, and the other body is made of a material different from the iron-based metal material, heat treatment being not required in the different material.

There are provided a variable compression-ratio mechanism (20) capable of varying an engine compression ratio in accordance with a rotational position of a control shaft (24); a speed reducer (44) configured to reduce in speed a rotational power of an actuator and transmit the speed-reduced rotational power to the control shaft (24); and a speed-reducer accommodating case (43) accommodating the speed reducer (44). An input shaft of the speed reducer (44) which is connected to the actuator has a shaft center line extending along a horizontal direction, and at least a part of the input shaft is kept under a lubricating oil retained in the speed-reducer accommodating case (43). The input shaft of the speed reducer (44) is swung by a predetermined swing angle to avoid inadequate lubrication of the input shaft of the speed reducer (44), during an operating state where the engine compression ratio is maintained constant.

Control device and control method for variable compression ratio internal combustion engines

The objective of the present invention is to improve the lubrication of a reduction gear interposed between a variable compression ratio motor and a control shaft (14) of a variable compression ratio mechanism. The present invention is provided with: a variable compression ratio mechanism that can change the engine compression ratio in accordance with the rotational position of a control shaft (14); a reduction gear that reduces the rotation of the motor and transmits the result to the control shaft (14); and a housing (22) for attaching the motor and the reduction gear to the side wall (7) of the engine main body. Lubricating oil is provided via a bypass oil pathway to a reduction gear housing chamber that is within the housing (22) and at which the lubrication position of the reduction gear is disposed. An oil hole (66) that interconnects with the reduction gear housing chamber is formed penetrating an auxiliary shaft (30) configured integrally with the output shaft of the reduction gear, and the oil surface height (G1) within the reduction gear housing chamber at the time of a low compression ratio is higher than the oil surface height (G2) within the reduction gear housing chamber at the time of a high compression ratio.

Lubrication structure for variable compression ratio internal combustion engine

An internal-combustion engine having a variable compression ratio includes a variable compression ratio mechanism for changing the engine compression ratio on the basis of the rotational position of a control shaft and an actuator for rotating the control shaft. The actuator is secured, with a plurality of securing bolts, to an actuator mounting part (40) provided on a side wall at the intake side of an upper oil pan (12), which is an engine body. A first rigidity improvement part (41) and a second rigidity improvement part (42) for improving the rigidity of the actuator mounting part (40) are provided within the inter-bolt distance (46) between the two securing bolts positioned at both sides in the crank shaft direction among the plurality of securing bolts.

Actuator mounting structure for internal-combustion engine having variable compression ratio

PROBLEM TO BE SOLVED: To securely prevent a valve lift changing mechanism 13 and a valve timing changing mechanism 17 from lowering in action responsiveness owing to rising in oil temperature or lowering in oil pressure. SOLUTION: The mechanism is provided with the valve lift mechanism (VVL) 13 for gradually changing the valve lift amount of a suction valve and the valve timing changing mechanism (VTC) 17 for continuously changing the valve timing of the suction valve 15. When oil pressure of an oil pump 31 is lower than the set oil pressure or oil temperature is higher than the set oil temperature in an operating range to operate both VVL13 and VTC17, oil pressure supply from a VVL solenoid 11 to VVL13 is prohibited. COPYRIGHT: (C)2005,JPO&NCIPI

Takagi Yusuke

Papers

Variable compression ratio internal combustion engine

Control device and control method for variable compression ratio internal combustion engines

Lubrication structure for variable compression ratio internal combustion engine

Actuator mounting structure for internal-combustion engine having variable compression ratio

Adjustable valve mechanism of internal combustion engine