US-12623576-B2 - Vehicle seat back frame member with adjustable stiffness system and method

US12623576B2US 12623576 B2US12623576 B2US 12623576B2US-12623576-B2

Abstract

Systems and methods for varying stiffness of a structural member. A vehicle seat includes the structural member. The structural member has two walls. A link extends between the walls and has three segments, with one segment extending between the other two. Connectors are disposed between disposed between the other two segments of the link and two walls of the structural member. The connectors may be adjustable to vary tension in the link and to vary stiffness of the structural member.

Inventors

Eryk Jerzy Dabrowski
Hans Sherman Grohs

Assignees

GM Global Technology Operations LLC

Dates

Publication Date: 20260512
Application Date: 20231204

Claims (20)

1 . A system with adjustable stiffness, the system comprising: a vehicle seat; a structural member of the vehicle seat, the structural member including a channel configured to provide the stiffness to the structural member, the structural member having a first wall and a second wall, wherein the structural member includes an angle extending from the second wall and configured to increase the stiffness; a link extending between the first wall and the second wall, the link having a first segment, a second segment and a third segment; a first connector disposed between the first segment of the link and the first wall of the structural member; and a second connector disposed between the third segment of the link and the second wall, 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, wherein the link is configured to increase or decrease the stiffness.
2 . The system of claim 1 , comprising: a head restraint of the vehicle seat coupled with the structural member; and a frame in the vehicle seat, wherein the structural member comprises a part of the frame.
3 . The system of claim 1 , wherein: the structural member forms a pocket, and the link is disposed in the pocket.
4 . The system of claim 1 , comprising a web and a third wall, wherein: the first wall comprises a first leg of the structural member, the third wall comprises the web, the second wall comprises a second leg of the structural member, the web extends between the first leg and the second leg forming a C-shape, and the link is connected with the first leg, with the web and with the second leg.
5 . The system of claim 1 , wherein: the vehicle seat has a back, and the structural member comprises an upper cross member of the back.
6 . The system of claim 1 , comprising a head restraint on the vehicle seat, wherein the at least one of the first connector and the second connector is configured to tune the stiffness to balance a response of the head restraint to expected forces with a response of the head restraint to rebound forces.
7 . The system of claim 1 , wherein the link comprises a stamping and is disposed to extend along the structural member.
8 . The system of claim 1 , wherein the channel includes a pair of openings configured to receive shafts of a head restraint.
9 . The system of claim 1 , wherein the first and second connectors are configured to place the link in either the tension or a compression.
10 . The system of claim 1 , wherein the first and second connectors comprise first and second threaded fasteners.
11 . 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.
12 . The system of claim 11 , comprising: a head restraint of the vehicle seat; and at least one shaft coupling the head restraint with the frame at the structural member.
13 . The system of claim 11 , wherein: the link is disposed in the pocket.
14 . The system of claim 11 , wherein the link is formed with five segments including the first segment, the second segment, the third segment, a fourth segment and a fifth segment, wherein each of the five segments is substantially planar, wherein the link is sized to be received within the pocket.
15 . The system of claim 11 , wherein: the vehicle seat has a back, and the structural member is disposed in the back and comprises an upper cross member of the frame.
16 . The system of claim 11 , comprising a head restraint on the vehicle seat, wherein both the first connector and the second connector are configured to tune the stiffness to balance a response of the head restraint to expected forces with a response of the head restraint to rebound forces.
17 . The system of claim 11 , wherein the link comprises a metal stamping and is disposed to extend along the structural member in a horizontal direction.
18 . The system of claim 11 , wherein: the structural member includes a channel configured to provide the stiffness to the structural member, the structural member includes an angle extending from the channel and configured to increase the stiffness, and the link is configured to increase the stiffness in addition to the increase of the angle.
19 . 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.
20 . The method of claim 19 , comprising: forming the structural member with five segments including the first segment, the second segment, the third segment, a fourth segment and a fifth segment, wherein each of the five segments is substantially planar.

Description

INTRODUCTION The present disclosure generally relates to vehicle seats with a frame made of structural members and more particularly relates to structural seat members with adjustable stiffness. A vehicle seat is designed for structural integrity and performance under a wide range of anticipated and potential loading scenarios that may arise during operation of the vehicle. Various seat design parameters have an effect on both structural integrity and occupant kinematic response. When a vehicle in which an occupant is seated experiences a sudden and rapid forward acceleration, the head of the occupant may tilt to the rear followed up by a reversed tilt back to the front in reaction thereto. The seat and its head restraint may be helpful in minimizing the tilting action and therefore in influencing the occupant's kinematic response. Design parameters for a desired performance may be determined during product development using modelling and testing. Once determined, the seat's components may be tailored to each seat and vehicle combination. For each application, certain component parts of the seat are unique and cannot generally be reused in other applications without design changes. Accordingly, it is desirable to provide vehicle seats with structural members that meet a range of different performance requirements. In addition, the structural members of the vehicle seats may preferably be reusable in a variety of applications without requiring redesigning. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing introduction. SUMMARY Systems and methods are provided for varying stiffness of a structural member. A vehicle seat includes the structural member. The structural member has two walls. A link extends between the walls and has three segments, with one segment extending between the other two. Connectors are disposed between disposed between the other two segments of the link and two walls of the structural member. The connectors may be adjustable to vary tension in the link and to vary stiffness of the structural member. The number of walls, links, and/or connections is not limited to the aforementioned example, but may be a variety of combinations as it relates to the varying stiffness of the structural member. In additional embodiments, a head restraint of the vehicle seat is coupled with the structural member and a frame is included in the vehicle seat, where the structural member comprises a part of the frame. In additional embodiments, the structural member includes a channel forming a pocket, and the link is disposed in the pocket. In additional embodiments, the structural member includes a web and a third wall. The structural member includes a channel forming a pocket. One wall is a leg of the channel. Another wall is the web. The third wall is a second leg of the channel. The web extends between the two legs forming a C-shape. The link is connected with the two legs and with the web. In additional embodiments, the vehicle seat has a back and the structural member is an upper cross member of the back. In additional embodiments, a head restraint is included on the vehicle seat, where the connector(s) is/are configured to tune the stiffness to balance a response of the head restraint to expected forces with a response of the head restraint to rebound forces. In additional embodiments, the link is a stamping and is disposed to extend along the structural member. In additional embodiments, the structural member includes a channel configured to provide the stiffness to the structural member. The structural member includes an angle extending from the channel and configured to increase the stiffness. The link is configured to increase the stiffness. In additional embodiments, the connectors are configured to place the link in either the tension and a compression. In additional embodiments, the connectors are threaded fasteners. In a number of other embodiments, a system with adjustable stiffness includes a vehicle seat having a frame. A structural member of the frame of the vehicle seat has two walls. A link extends between the walls. The link has three segments, where one middle segment extends between the other two outside segments. One outside segment is disposed along one wall of the structural member and the other outside segment is disposed along the other wall of the structural member. One connector is engaged between a segment of the link and a wall of the structural member. Another connector is engaged between another segment of the link and another wall of the structural member. At least one connector is adjustable to vary tension in the middle segment of the link and to vary stiffness of the structural member. In additional embodiments, a head restraint is included on the vehicle seat. A shaft couples the head r