Toyota Jidosha Kabushiki Kaisha

Yoshirou Kamo

Yoshihito Moriya

Haruhito Fujimura

Atsushi Hayashida

A variable valve timing apparatus includes: a variable valve timing mechanism that changes a valve timing and locks the valve timing at a most retarded timing; an oil control valve that controls a mode in which hydraulic fluid is supplied to the variable valve timing mechanism; and a controller that varies a duty ratio of the oil control valve within a set range that includes an advance active band, a retard active band, a holding range, an advance release range and a retard release range. In the advance release range, a varying speed of the valve timing is higher than the holding range and a housing rotor is disengaged from a vane rotor. When an engine operating state is a release request state, the controller sets the duty ratio of the oil control valve within the advance release range.

Growing community of inventors

Toyota, Japan

Yoshirou Kamo