Patent attributes
An internal combustion engine includes a control shaft, an actuator, and an oil accumulation portion. The control shaft is configured to vary a lift amount of an engine valve in accordance with a rotational position of the control shaft. The actuator is configured to drive the control shaft to make the lift amount of the engine valve to be a start lift amount before the engine is started. The actuator includes a worm wheel and a worm. The worm wheel is provided at the control shaft and is disposed in an engine body. The worm is disposed below the control shaft and engages with the worm wheel. The oil accumulation portion is provided at at least one of the control shaft and the worm wheel and is configured to drop oil onto the worm in accordance with the rotation of the control shaft when the engine is started.
