Patent ID: 7517015
Filing Date: 2009-04-14
Classification: B60N

Abstract:
1. A headrest device, comprising: a fixed base being supported by a seatback; a movable base disposed at a forward position relative to the fixed base; at least one first link being rotatably supported by a connecting shaft provided between the movable base and the fixed base, the first link having a first end connected to the movable base and a second end connected to the fixed base; at least one second link being supported by the connecting shaft so as to rotate relative to the first link, the second link having a first end connected to the movable base and a second end connected to the fixed base; a connection portion including the first link and the second link and connecting the movable base and the fixed base to be relatively movable by a relative rotation between the first link and the second link; a drive portion relatively rotating the first link and the second link in a direction so as to deploy the movable base away from the fixed base on the basis of a detected result by a rear-end collision detection means which is connected to the connection portion to detect and/or predict a vehicle rear-end collision; at least one relative rotation restricting portion provided at a portion of the fixed base and/or the movable base; and a biasing portion for biasing the first link away from the at least one relative rotation restricting portion, the at least one relative rotation restricting portion restricting a relative rotation between the first link and the second link about the connecting shaft when a load larger than a biasing force of the biasing portion is applied to the movable base upon the vehicle rear-end collision and when subsequent rearward movement of the movable base establishes an engagement thereof with the first link, the at least one relative rotation restricting portion allowing the relative rotation between the first link and the second link about the connecting shaft when the load applied to the movable base is smaller than the biasing force of the biasing portion and when the resulting disengagement of the movable base from the first link is established.