Abstract: A valve opening and closing time detecting apparatus and method of an elecromagnetically operated valve in an internal combustion engine comprises a vibration detecting means for detecting a vibration generated when the valve reaches a fully open position or when the valve reaches a valve seated position and a judging means for comparing a comparison data obtained from the vibration detecting means with a threshold value and for judging that the valve has reached the open position or the seated position when the comparison data exceeds the threshold value.

Abstract: An electromagnetic valve has a first and a second electromagnetic coil and an armature. The first electromagnetic coil generates a magnetic filed to cause the armature to move a valve for closing. The second electromagnetic coil generates a magnetic filed to cause the armature to move the valve for opening. The first electromagnetic coil is energized to generate the magnetic field. Measurement of time at a first moment is started before the valve is moved to a first position at which the first electromagnetic coil is temporarily de-energized and to output a first signal after a predetermined period of time has passed from the first moment. The temporarily de-energized first electromagnetic coil is energized in response to the first signal. The first electromagnetic coil is de-energized when the valve is fully closed. The second electromagnetic coil is energized to generate the magnetic field after the first electromagnetic coil is de-energized.

Abstract: An electromagnetically operated valve driving system for driving an intake or exhaust valve of an engine comprises an opening solenoid, a closing solenoid, and a control apparatus for energizing or deenergizing these opening and closing solenoids. Springs are provided in order to balance a valve body on a specified position between the fully open and fully closed positions. Further, when the intake or exhaust valve is closed, the closing solenoid is deenergized for a very short time immediately before the intake or exhaust valve is fully closed so as to reduce a traveling speed of the valve body when said valve body is seated. Also, when the intake or exhaust valve is opened, the opening solenoid is deenergized for a very short time immediately before the intake or exhaust valve is fully opened so as to reduce a traveling speed of the valve body when the valve body is fully opened.

Abstract: During idling of an internal combustion engine, when there is a difference between an actual engine speed and a target idle speed which is preset in accordance with an engine load, the opening and closing timings of an intake/exhaust valve of the engine is changed in accordance with the difference between the actual engine speed and the target idle speed to change an intake air flow sucked into the engine. Therefore, it is not required to provide any apparatus, such as an ISC valve, provided in conventional systems, and it is possible to quickly adjust the engine speed so as to be equal to the target idle speed.

Abstract: A valve mechanism has a low-speed cam and a high-speed cam, a low-speed rocker arm operatively connected with a valve and a high-speed rocker arm. A changeover pin is provided for connecting the low-speed rocker arm and the high-speed rocker arm to each other so as to be rocked together by the high-speed cam. The changeover pin is slidably mounted in the high-speed rocker arm. A flat engaging face is formed on a front portion of the changeover pin so as to be engaged with a shaft provided for connecting both of the rocker arms.

Abstract: A control system for an internal combustion engine having an air pump provided in an intake passage for supplying air into a cylinder of the engine. A continuously variable belt-drive automatic transmitting device is provided between a crankshaft of the engine and a drive shaft of the air pump. The transmitting device control unit is controlled by a control unit in accordance with operating conditions of the engine. A throttle valve is provided upstream of the air pump.

Abstract: An intake air control system for an automotive engine having a turbocharger has a bypass provided around a compressor of the turbocharger and a control valve provided in the bypass. The control valve is connected to an accelerator pedal by a connecting mechanism. The connecting mechanism is so arranged that the control valve is opened in a low engine speed range and closed in a high engine speed range.

Abstract: A reciprocating internal combustion engine has a head block axially slidably mounted in a bore formed in a cylinder block in alignment with the cylinder bore, and a cam for moving the head block in the bore in accordance with the position of the piston. The crankshaft of the engine is laterally offset from the axis of the cylinder bore by the length of the crank radius. The cam is so arranged that the motoring pressure becomes maximum at the crank angle of 90 degrees.