US 2009/0211548 A1 · VARIABLE VALVE DEVICE FOR ENGINE

Abstract

A variable valve device, which is capable of automatically canceling a deviation in the relationship between the rotation angle of a control shaft and the lift degree generated because of the disassembling and assembling of an engine, includes a target lift degree calculator that calculates a target lift degree, a motor driver that drives a brushless DC motor that rotates the control shaft until the lift degree reaches the target lift degree, and an automatic deviation canceller that automatically cancels the deviation. More specifically, the magnetic pole pulse pattern of the motor before the engine starts is obtained and it is determined whether the pattern match magnetic pole pulse pattern stored before the engine stops. If they do not match, an idle lift degree is set, the idle lift degree is changed so that the engine speed is within the tolerance range of an idle engine speed, the rotation angle for the idle portion is subtracted from the obtained angle of the control shaft and a reference angle is updated by the difference.

Claims10

Dependent claims

A variable valve device comprising:

a control shaft arranged to change a lift degree of an intake valve in an engine;
an angle specifying information obtainer arranged to obtain angle specifying information specifying a rotation angle of the control shaft;
and
a changer arranged to change an adjustment angle if an information difference between the angle specifying information obtained by the angle specifying information obtainer before the engine starts and a predetermined reference angle specifying information is not within a predetermined information range;
wherein
the adjustment angle is the rotation angle of the control shaft after the engine starts and while an accelerator is not operated.

3 more elements

Dependencies are inferred from the claim text.

Variable valve device for engine

Life of this patent

Variable valve device for engine

Life of this patent

Abstract

Claims10