Air vent for vehicle

An air vent system for a vehicle, comprising:

• a housing comprising a blower duct;
• a damper configured to open and close the blower duct;
• a wing member attached to the housing and configured to adjust a blowing direction of air from the blower duct;
• a damper knob coupled to the wing member, the damper knob being configured to move when the wing member moves and further configured to rotate for causing the damper to open and close the blower duct;
• and
• an opening-closing interlock connecting the damper and the damper knob,
• wherein the damper comprises a driven gear and a damper rotating member that is rotary about a central axis and configured to rotate the driven gear,
• wherein the opening-closing interlock comprises a knob shaft, a pivot link, a connection link and a shaft positioner that are arranged in order between the damper knob and the damper rotating member for transmitting the damper knob's rotation from the damper knob to the shaft positioner,
• wherein the knob shaft is fixed to the damper knob to move along with the damper knob, wherein the knob shaft is hingedly coupled to the pivot link to transmit the damper knob's rotation to the pivot link while allowing the knob shaft to pivot with respect to the pivot link about a first hinge axis,
• wherein the pivot link is hingedly coupled to the connection link to transmit the damper knob's rotation to the connection link while allowing the pivot link to pivot with respect to the connection link about a second hinge axis,
• wherein the connection link is pivotally coupled to the shaft positioner via a ball joint and engaged with the shaft positioner via protrusion-groove engagement such that the connection link is configured to transmit the damper knob's rotation to the shaft positioner while allowing the connection link to pivot with respect to the shaft positioner,
• wherein the shaft positioner is coupled to the damper rotating member to transmit the damper knob's rotation to the damper rotating member.