Aisin Seiki Kabushiki Kaisha

Takashi Iwaya

Hiroyuki Amano

Koji Nunami

Masaki Kobayashi

Yuji Noguchi

Shigehiro Tanabe

A variable valve timing control device includes a phase detecting portion; a phase control portion driving an electromagnetic solenoid while obtaining a detection signal detected by the phase detecting portion to set a spool to one of a phase control region and a lock region; and a boundary memory portion memorizing a boundary electric current value for referring a boundary between the phase control region and the lock region when the phase control portion operates a phase control; and a characteristic calculation portion obtaining the boundary electric current value by calculation, the boundary electric current value supporting the boundary between the phase control region and the lock region based on solenoid characteristic information of the electromagnetic solenoid and valve characteristic information of an electromagnetic control valve, the characteristic calculation portion memorizing the boundary electric current value to the boundary memory portion.

Variable valve timing control device

A system for controlling valve opening/closing timing that allows an unlocking operation to be reliably performed is configured. When extracting a lock member from a recess, a second control valve is set to an unlock position, a first control valve is set to a predetermined position, and a relative rotation phase is displaced. As a result, the relative rotation phase is displaced in a direction opposite to the direction of displacement by cam average torque from a camshaft. Afterward, by setting the first control valve to a neutral position, the relative rotation phase is displaced by the cam average torque, and when this displacement occurs, a state in which the lock member is separated from an inner wall of the recess is created, thus facilitating extraction of the lock member from the recess.

System for controlling valve opening/closing timing

A valve opening/closing timing control device includes: an intermediate lock mechanism switchable between a locked state constraining a relative rotation phase to an intermediate locked phase, and an unlocked state releasing the constraint; a phase control unit controlling fluid supply to a retard chamber and fluid discharge from an advance chamber, or controlling fluid discharge from the retard chamber and fluid supply to the advance chamber, such that the lock member attains the intermediate locked phase; and a determination unit determining whether the lock member will attain the determination phase, when control has been performed to move the lock member toward a determination phase that has been set at a different position than the intermediate locked phase, after execution of control to either supply fluid to the retard chamber and discharge fluid from the advance chamber, or discharge fluid from the retard chamber and supply fluid to the advance chamber.

Growing community of inventors

Obu, Japan

Takashi Iwaya