Patent ID: 8132858

Claim:
A vehicle seat comprising: a seat back frame having right and left side frames; a headrest mounted to the seat back frame; a rear-end collision detector mounted to the seat back frame, wherein the rear-end collision detector detects rearward movement of a seat occupant and moves rearward; and the rear-end collision detector acts such that the rearward movement of the rear-end collision detector reduces a distance between a head of the seat occupant and the headrest; a respective support shaft mounted to each side frame; a support member that supports the support shaft; a link member mounted to the support shaft; and a biasing member that biases the link member; wherein: a lower portion of the link member is connected to the rear-end collision detector; each of the side frames is provided with a front projecting wall inwardly projecting and integrally formed at a front end of the respective side frame, and a rear projecting wall inwardly projecting and integrally formed at a rear end of the respective side frame; each of the side frames comprises a lateral face, the lateral face comprising a concave portion that is indented or concave in a direction towards the other side frame; at least a part of the support member is attached to the concave portion; the concave portion is provided with an opening and a support member attachment portion for attaching the support member; and the opening is disposed above the support member attachment portion.