Valve timing adjusting device

A valve timing adjusting device provided in a transmission system for the transfer of a driving torque of a drive shaft in an internal combustion engine to a driven shaft which actuates at least one of an intake valve and an exhaust valve for opening and closing motions, to adjust an opening/closing timing of the at least one of the intake valve and the exhaust valve, the valve timing adjusting device comprising:

• a rotatable member adapted to rotate about an axis of the driven shaft with the driving torque of the drive shaft, the rotatable member having an internal gear concentrically with an axis of the driven shaft;
• an eccentric shaft eccentric to the axis of the driven shaft and adapted to rotate about the axis of the driven shaft with rotation of the rotatable member;
• a planetary gear supported by an outer periphery wall of the eccentric shaft so as to be relatively rotatable about an axis of the eccentric shaft and adapted to rotate about the axis of the driven shaft with rotation of the rotatable member by meshing with the internal gear;
• an output shaft connected to the driven shaft and adapted to rotate about the axis of the driven shaft integrally with the driven shaft with rotation of the planetary gear by engagement with the planetary gear;
• an operating shaft connected to the eccentric shaft and adapted to rotate about the axis of the driven shaft integrally with the eccentric shaft;
• and
• an electromagnetic unit fixed to the internal combustion engine so as not to be displaced, the electromagnetic unit causing a magnetic field to be generated along an outer periphery of the operating shaft by the supply of an electric current and thereby applying to the operating shaft a first torque acting in a direction opposite to the rotational direction of the operating shaft and a second torque acting in the rotational direction of the operating shaft,
• wherein when the electromagnetic unit applies the first torque to the operating shaft in a rotating state of the shaft, the operating shaft and the eccentric shaft rotate relatively in a delay direction with respect to the rotatable member, whereby the planetary gear rotates relatively in an advance direction together with the output shaft and the driven shaft with respect to the rotatable member while rotating relatively in the advance direction with respect to the eccentric shaft, and
• when the electromagnetic unit applies the second torque to the operating shaft in a rotating state of the shaft, the operating shaft and the eccentric shaft rotate relatively in the advance direction with respect to the rotatable member, whereby the planetary gear rotates relatively in the delay direction together with the output shaft and the driven shaft with respect to the rotatable member while rotating relatively in the delay direction with respect to the eccentric shaft.