WO2002022399A2

WO2002022399A2 - Energy dissipating vehicle seat

Info

Publication number: WO2002022399A2
Application number: PCT/US2001/029058
Authority: WO
Inventors: Pascal Emanuel Garrido
Original assignee: Dura Global Technologies, Inc.
Priority date: 2000-09-18
Filing date: 2001-09-18
Publication date: 2002-03-21
Also published as: WO2002022399A3; WO2002022399A9

Abstract

A vehicle seat assembly (10) includes a lower seat frame (12), a seat back (14) pivotally connected with respect to the lower seat frame (12), and a recliner mechanism (16) secured between the seat back (14) and the lower seat frame (12) for adjusting the angle of the seat back (14) relative to the lower seat frame (12). An attachment bracket (18) is secured between lower seat frame (12) and the recliner mechanism (16). The attachment bracket (18) is adapted to behave as a four-bar linkage in a vehicle collision when a force is applied to the seat backe (14). The attachment bracket (18) preferably includes a top member (18a) secured to the seat backe (14), a bottom member (18b) secured to the lower seat farme (12), and front and back members (18c, 18d) connecting the ends of the top and bottom members (18a, 18b). Various embodiments are disclosed wherein the top, bottom, front, and back members (18a, 18b, 18c, 18d) are separate members joined by pivoting joints (19) or part of a one-piece member joined by zones of deformable material.

Description

PATENT

ENERGY DISSIPATING VEHICLE SEAT

FIELD OF THE INVENTION The present invention generally relates to a reclining vehicle seat assembly and, . more particularly, to such a seat assembly having a bracket dissipating energy of a seat back with respect to the lower seat frame in a collision having a high energy impact.

BACKGROUND OF THE INVENTION In a collision having high energy impact, large forces may be delivered to the occupant of a vehicle seat. In a rearward impact, the occupant is forced against the seat, and may experience a large energy pulse. In a forward impact, if vehicle seats incorporate a belt restraint system into the seat back, the occupant is forced against the belt restraint and may experience a large energy pulse. Attempts have been made to provide a vehicle seat assembly which is adapted to dissipate energy of an occupant in a high energy impact to prevent the occupant from experiencing an excessive energy pulse during deceleration. For example, see U.S. Patent Nos. 5,676,421 and 5,733,722, the disclosures of which are expressly incorporated herein in their entirety by reference, which each disclose vehicle seat energy absorbing mechanisms. While these attempts may be somewhat effective in reducing the energy pulse seen by the occupant, they are relatively complex and expensive" to produce. Accordingly, there is a need in the art for an improved vehicle seat assembly which reduces the energy pulse seen by the occupant, reduces energy transferred to the vehicle floor, and is relatively simple inexpensive to produce.

SUMMARY OF THE INVENTION The present invention overcomes at least some of the problems of the related art by providing a vehicle seat assembly comprising, in combination, a lower seat frame, a seat back pivotally connected with respect to the lower seat frame, and a recliner mechanism secured between the seat back and the lower seat frame for adjusting the angle of the seat back relative to the lower seat frame. An attachment bracket is secured between lower seat frame and the recliner mechanism. The attachment bracket is adapted to behave as a four- bar linkage in a vehicle collision when a force is applied to the seat back. The attachment bracket can be adapted to move the seat back rearwardly and downwardly in a collision without pivoting the seat back relative o the recliner mechanism. From the foregoing disclosure and the following more detailed description of various preferred embodiments it will be apparent to those skilled in the art that the present invention provides a significant advance in the art of vehicle seats. Particularly significant in this regard is the potential the invention affords for providing a high quality, reliable low cost seat assembly which is particularly adaptable for use in motor vehicles. Additional features and advantages of preferred embodiments will be better understood in view of the detailed description provided below.

BRIEF DESCRIPTION OF THE DRAWINGS These and further features of the present invention will be apparent with reference to the following description and drawings, wherein: FIG. 1 is schematic view of a vehicle seat assembly according to the present invention; FIG. 2 is a schematic view showing collapse of a prior art vehicle seat assembly during a crash situation having a high energy impact; FIG. 3 is a schematic view, similar to FIG. 2, but showing collapse of the vehicle seat assembly of FIG. 1 during a crash situation having a high energy impact; FIG. 4 is an enlarged, fragmented view of the prior art vehicle seat assembly of FIG. 2 showing the recliner attachment bracket; FIG. 5 is an enlarged, fragmented view, similar to FIG. 4, of the vehicle seat assembly of FIGS 1 and 3, showing a recliner attachment bracket having a four-bar linkage configuration; and FIG. 6 is an enlarged, fragmented view, similar to FIGS. 5, but showing a one-piece, stamped, recliner attachment bracket according to the present invention which behaves like the bracket of FIG. 5 having four-bar linkage configuration under a crash situation with a high energy impact. It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of the vehicle seat assembly assemblies as disclosed herein, including, for example, specific dimensions, orientations, and shapes of the bracket will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration. All references to direction and position, unless otherwise indicated, refer to the orientation of the vehicle seat assembly illustrated in the drawings. In general, up or upward refers to an upward direction in of the plane of the paper in FIG. 1 and down or downward refers to a downward direction in the plane of the paper in FIG. 1. In general, forward refers to a left direction in the plane of the paper in FIG. 1 and rearward refers to a right direction in the plane of the paper in FIG. 1.

DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS It will be apparent to those skilled in the art, that is, to those who have knowledge or experience in this area of technology, that many uses and design variations are possible for the improved vehicle seat assembly disclosed herein. The following detailed discussion of various alternative and preferred embodiments will illustrate the general principles of the invention with particular reference to seat assemblies for use with a motor vehicle. Other embodiments suitable for other applications will be apparent to those skilled in the art given the benefit of this disclosure. Referring now to the drawings, FIG. 1 schematically illustrates a vehicle seat assembly 10 according to the present invention. The vehicle seat assembly 10 includes a seat bottom or lower seat frame 12, and a seat back 14 pivotally attached to the lower seat frame 12 by a recliner mechanism 16. The recliner mechanism 16 forms a horizontally and transversely extending pivot axis for the seat back 14 so that the angular position of the seat back 14 relative to the lower seat frame 12 can be adjusted by the occupant. The recliner mechanism 16 is secured to the lower seat frame 12 by a recliner attachment bracket 18. A lower end of the recliner attachment bracket 18 is rigidly secured to the lower seat frame 12. An upper end of the attachment bracket 18 is rigidly secured to the recliner mechanism 16. The seat back 14 is secured to the recliner mechanism 16 so that the recliner mechanism 16 connects the seat back 14 to the attachment bracket 18 and the attachment bracket 18 connects the reclining mechanism 16 to the lower seat framel2. The attachment bracket 18 is in the configuration of a four-bar linkage such that it collapses in a desired manner during a collision as described in more detail hereinafter. The illustrated attachment bracket has generally horizontal top and bottom bar members 18a, 18b which are connected at their ends by substantially vertical front and back bar members, each of the bar members are connected by a joint 19 which is pivotable upon predetermined loading indicating a vehicle crash. The joint 19 can be of any suitable type such as, for example, a pivot or a deformation zone. The seat back 14 is generally rigidly connected to the top bar member 18a and the bottom bar member 18b is generally rigidly connected to the seat frame 12. FIG. 2 schematically illustrates the behavior of a prior art vehicle seat assembly 100 during a rear end collision having a high energy impact. The prior art seat assembly 100 is generally the same as the vehicle seat assembly 10 described hereinabove with regard to FIG. 1 except that a generally rigid attachment bracket 20 secures the recliner mechanism 16 to the lower seat frame 12. When a rearward force 22 is applied to the seat back 14 due to the high energy impact, the seat frame collapses in a pure bending fashion. That is, the seat back 14 pivots in a rearward direction about the pivot axis and relative to the attachment bracket 20 and seat frame 12. FIG. 3 schematically illustrates the behavior of the vehicle seat assembly 10 of FIG. 1 during a rear end collision having a high energy impact. When the rearward force 22 is applied to the seat back 14 due to the high energy impact, the recliner attachment bracket 18 fails in a controlled manner. The illustrated recliner attachment bracket 18 behaves as a four-bar linkage such that the seat back 14 pivots such that it moves in a rearward and downward direction wherein it remains generally in the same angular orientation relative to the lower seat frame 12, that is, the seat back does not pivot about the pivot axis of the recliner mechanism. The connection between the top bar 18a and the seat back 14 remains rigid to generally prevent movement therebetween and the connection between the bottom bar member 18b remains generally rigid to generally prevent movement therebetween. The controlled movement of the four-bar linkage is provided by the pivoting movement of the front and back bar members 18c, 18d relative to the top and bottom bar members 18a, 18b. The pivoting movement being provided at the pivoting j oints 19. It is noted that while FIG. 3 illustrates behavior during a rear end collision, the attachment bracket 18 can be adapted for similar advantageous behavior in front end collisions when the occupant seat belt is secured to the seat back 14, head rest, or other seat assembly component such that a forward force is applied to the seat back 14 from the occupant through the seat belt. FIG. 4 is an enlarged view of the generally rigid attachment bracket 20 of the vehicle seat assembly 100 of FIG. 2. FIG. 5 is an enlarged view of the recliner attachment bracket 18 of the vehicle seat assembly 10 of FIGS. 1 and 3 wherein the attachment bracket 18 has a four-bar linkage configuration. The attachment bracket 18 is designed to behave the same as the prior art attachment bracket 20 during normal operating conditions of the vehicle seat assembly 10 but is designed to collapse as described hereinabove during collisions. FIG. 6 illustrates that the attachment bracket 18 can be a one-piece member, that is, a unitary member of continuous material without having pivoting joints like a four-bar linkage. The illustrated single piece attachment bracket 18 has a generally square-tube shape in cross- section. Generally parallel and offset top and bottom members 24, 26 are connected by generally parallel and offset side members 28, 30 which connect the ends of the top and bottom members 24, 26. The top member 28 is attached to the reclining mechanism 16 while the lower member 26 is attached to the lower seat frame 12. The one-piece attachment member 18 is sized and shaped to behave like the four-bar linkage during collisions. The one piece attachment bracket 18 can be made of any suitable material such as, for example, a steel, and can be formed by any suitable process such as, for example, stamping. It is noted that the one piece attachment bracket can also take many other suitable shapes. It should be appreciated from the forgoing description that the vehicle seat assembly 10 may reduce injuries to the occupant and may reduce energy transmitted to the floor of the vehicle resulting in reduced weight and cost. From the foregoing disclosure and detailed description of certain preferred embodiments, it will be apparent that various modifications, additions and other alternative embodiments are possible without departing from the true scope and spirit of the present invention. For example, it will be apparent to those skilled in the art, given the benefit of the present disclosure, that the attachment bracket 18 can each have many different configurations and materials. The embodiments discussed were chosen and described to provide the best illustration of the principles of the present invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the present invention as determined by the appended claims when interpreted in accordance with the benefit to which they are fairly, legally, and equitably entitled.

Claims

WHAT IS CLAIMED IS :

1. A vehicle seat assembly comprising, in combination: a lower seat frame; a seat back pivotally connected with respect to the lower seat frame; a recliner mechanism secured between the seat back and the lower seat frame for adjusting the angle of the seat back relative to the lower seat frame; and an attachment bracket secured between lower seat frame and the recliner mechanism, wherein the attachment bracket is adapted to behave as a four-bar linkage in a vehicle collision causing a force to be applied to the seat back.

2. The vehicle seat according to claim 1, wherein the attachment bracket includes a top member secured to the seat back, a bottom member secured to the lower seat frame, and front and back members connecting the ends of the top and bottom members.

3. The vehicle seat according to claim 2, wherein the top, bottom, front, and back members are joined by pivoting joints.

4. The vehicle seat according to claim 2, wherein the top, bottom, front, and back members are j oined by zones of deformable material.

5. The vehicle seat according to claim 2, wherein the top member is rigidly connected to the recliner mechanism and the bottom member is rigidly connected to the lower seat frame.

6. The vehicle seat according to claim 2, wherein the top, bottom, front, and back members form a four-bar linkage.

7. The vehicle seat according to claim 2, wherein the attachment bracket is a one- piece member with the top, bottom, front, and back members are formed by continuous material.

8. The vehicle seat according to claim 1, wherein the attachment bracket is generally rectangularly-shaped in cross-section.

9. The vehicle seat according to claim 8, wherein the attachment bracket is a one- piece member.

10. The vehicle seat according to claim 9, wherein the attachment bracket is formed by a tube.

11. The vehicle seat according to claim 8, wherein the attachment bracket includes a top member secured to the seat back, a bottom member secured to the lower seat frame, and front and back members connecting the ends of the top and bottom members.

12. The vehicle seat according to claim 11, wherein the top member is rigidly connected to the recliner mechanism and the bottom member is rigidly connected to the lower seat frame.

13. The vehicle seat according to claim 12, wherein the top, bottom, front, and back members are joined by pivoting joints.

14. The vehicle seat according to claim 12, wherein the top, bottom, front, and back members are joined by zones of deformable material.