Vehicle seat back frame member with adjustable stiffness system and method

A system with adjustable stiffness, the system comprising:

• a vehicle seat having a frame;
• a structural member of the frame of the vehicle seat, the structural member forming a pocket and having a first wall comprising a first leg of the structural member, and a second wall comprising a second leg of the structural member, and a third wall comprising a web of the structural member, wherein the web extends between the first leg and the second leg so that the first leg, the web and the second leg form a channel-like C-shape around the pocket;
• a link extending between the first wall and the second wall, the link having a first segment, a second segment and a third segment, wherein the second segment extends between the first segment and the third segment, the first segment configured to be disposed along the first wall and the third segment configured to be disposed along the second wall;
• a first connector engaged between the first segment of the link and the first wall of the structural member;
• a second connector engaged between the third segment of the link and the second wall of the structural member;
• and
• a third connector engaged between the second segment of the link and the third wall of the structural member,
• wherein the link is connected with the first leg, with the web and with the second leg,
• wherein at least one of the first connector and the second connector is adjustable to vary tension in the second segment of the link and to vary stiffness of the structural member.

A method for adjustable stiffness, the method comprising:

• constructing a vehicle seat;
• including a head restraint on the vehicle seat;
• including a structural member in the vehicle seat, the structural member having a first wall and a second wall;
• extending a link between the first wall and the second wall, the link having a first segment, a second segment and a third segment, with the second segment extending between the first segment and the third segment;
• adding a first connector between the first segment of the link and the first wall of the structural member;
• adding a second connector between the third segment of the link and the second wall;
• and
• adjusting at least one of the first connector and the second connector varying tension in the second segment of the link and varying stiffness of the structural member;
• evaluating a balance between an expected force on the head restraint and a rebound force from the head restraint;
• determining a baseline stiffness of the structural member based on the evaluating the balance;
• creating a base design of the structural member to provide the baseline stiffness;
• adjusting the baseline stiffness with the link to provide the varying stiffness of the structural member;
• and
• reusing the base design in various applications that require different stiffnesses provided by the adjusting the baseline stiffness.