Abstract:
An energy absorbing assembly for a vehicle seat belt anchor. Two energy-absorbing members are carried on a seat belt anchor mounting bolt that connects an adjusting rail to a body pillar. One energy-absorbing member, upon contact with an object that is suddenly moving toward the bolt is initially crushed until the object contacts the adjusting rail. A second shock-absorbing member is disposed between the adjusting rail and the body pillar to absorb a continued motion of the object toward the body pillar.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     Automotive manufacturers cushion certain vehicle interior components, such as the seat belt anchors, near that portion of the vehicle where an occupant&#39;s head might impact the seat belt components. 
     Examples of prior art illustrating approaches to this problem, include U.S. Pat. No. 5,820,164 issued Oct. 13, 1998 to Rasik Patel and Francis Joseph Wickenheiser for “Energy Absorbing Seat Belt Component Fastener”; U.S. Pat. No. 6,106,012 issued Aug. 22, 2000 to Herbert Boegge et al. for “Deflection Fitting for Seat Belts of Vehicles”; U.S. Pat. No. 5,941,567 issued Aug. 24, 1999 to Francis J. Wickenheiser for “Head Impact Protection for an Automobile Seat Belt Anchor Fastener” and U.S. Pat. No. 5,529,344 issued Jun. 25, 1996 to Shinichi Yasui et al. for “Seat Belt Device for Automobile”. 
     The broad purpose of the present invention is to provide an improved seat belt anchoring device for reducing head injuries in a vehicle. In the preferred embodiment of the invention, the seat belt anchoring device comprises an elongated vehicle rail having a belt anchoring ring mounted in a slot. The position of the ring can be vertically adjusted to accommodate the tautness of the belt for the passenger. 
     The rail is mounted on a pair of vertically spaced bolts attached to a body pillar. The length of the bolts is such that the rail can be moved from its normal operating position toward the body pillar. Shock-absorbing (cushioning) elements are mounted on the rail and the bolts. One form of shock absorbing element encloses each bolt connecting the rail to the body pillar. An object suddenly moving toward the bolt encounters the vehicle trim, then crushes or deforms the shock-absorbing element to absorb part of the energy of the moving object. A second shock-absorbing element is mounted between the rail and the body pillar to accommodate a continued motion of the moving object toward the body pillar. The rail moves toward the body pillar crushing walls of both shock-absorbing elements, thereby absorbing further energy. 
     This arrangement also accommodates a condition in which the moving object does not impact the bolt but instead moves directly toward the seat belt rail or ring. In this condition, the rail, in response to the impact, moves toward the body pillar crushing walls of both shock-absorbing elements. 
     Still further objects and advantages of the invention will become readily apparent to those skilled in the art to which the invention pertains upon reference to the following detailed description. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     The description refers to the accompanying drawings in which like reference characters refer to like parts throughout the several views, and in which: 
     FIG. 1 is a view of an energy-absorbing seat belt anchoring device illustrating the preferred embodiment of the invention; 
     FIG. 2 is an elevational view of the anchoring device mounted on a vehicle body pillar, illustrated in section; 
     FIG. 3 is an enlarged sectional view of one of the bolts enclosed by the preferred shock-absorbing components; 
     FIG. 4 is similar to FIG. 3 but shows the shock-absorbing device elements crushed under a head impact; 
     FIG. 5 is another perspective sectional view of the preferred embodiment in its undeformed condition; 
     FIG. 6 is a blown-up view of the basic components of the preferred seat belt anchoring device; 
     FIG. 7 illustrates the outer shock absorber; 
     FIG. 8 illustrates the inner shock absorber; 
     FIGS. 9 and 10 illustrate other forms of the shock absorbers; and 
     FIGS. 11-13 illustrate a shock absorber using a viscous fluid material. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1 and 2 illustrate a preferred seat belt anchoring device  10  mounted on a flat panel section of a vehicle body pillar  12 . Referring to FIGS. 3 and 4, body pillar  12  is channel-shaped with a pair of lips  14  and  16  rigidly connected to a portion of vehicle frame  18 . Body pillar  12  has a relatively flat base wall  20 . 
     The preferred seat belt anchor includes an elongated channel-shaped metal rail  22  supported on the pillar  12  in a vertical position. The rail  22  supports a seat belt anchoring ring  24 . Anchoring ring  24  is fastened by fastening screw  26  to the rail  22  which permits ring  24  to be disposed in a desired vertical position along the length of the rail  22 , using any of the commonly employed adjusting mechanisms, for example, such as illustrated in U.S. Pat. No. 6,106,012 to Herbert Boegge et al. A pair of bolts  28  and  30  fasten the rail  22  to body pillar  12 . Bolt  28  has an elongated partially threaded shank  32  and a larger head  34 . Similarly bolt  30  has an elongated partially threaded shank  36  and a head  38 . The two bolts are identical and mounted in vertically spaced positions on the body pillar  12 . The two bolts as well as the belt-supporting ring components provide an area for injuring a suddenly moving vehicle occupant such as in the direction of arrow  39 A or arrow  39 B as shown in FIG.  2 . 
     Both bolts are enclosed by interior trim  40  as illustrated in FIGS. 3 and 4. A head impact will tend to move the interior trim toward the body pillar  12 . 
     Referring to FIGS. 3 and 4, bolt  28  is threadably fastened to base wall  20  of the body pillar, in a relatively fixed position. The bolt shank extends through an opening  42  in the rail  12 . Head  34  of the bolt is larger than the bolt opening. The rail  22  is movable along the shank of the bolt toward the body pillar from a position illustrated at “A” in FIG. 3 to a position illustrated at “B” in FIG.  4 . An outer shock-absorbing member  46  encloses the head and part of the shank of bolt  28 . Shock-absorbing member  46  has walls  48  that extend around the bolt  28  toward the body pillar. The shock-absorbing member  46  has a head  50  connected to walls  48 . 
     FIG. 6 shows how the end of rail  22  extends through an opening  52  in the outer shock-absorbing member  46 . Walls  48  of the outer shock-absorbing member are mounted perpendicular to pillar base wall  20 , parallel to the longitudinal axis of the bolt  28 . Head  50  of the outer shock-absorbing member  46  is spaced from the rail to permit the outer shock-absorbing member head to move toward the body pillar in a process in which walls  48  collapse or corrugate in a shock-absorbing manner, as illustrated in FIG. 4 at  59 . Upper lips  53   a  and  53   b  of the rail are movable along the shank of the bolt  28  toward the body panel until the lips are flush with the top of the bolt head. 
     A second or lower shock-absorbing member  54  is mounted between the bottom wall of the rail  22  and the body pillar  12 . The lower shock-absorbing member  54  has a plurality of walls  56  as best shown in FIGS. 5 and 6 that are parallel to the walls of the outer shock-absorbing member  46 . The lower shock-absorbing member has a wall  58  that engages the lower wall of the rail in such a manner that as the rail moves toward the body panel, walls  56  of the lower shock-absorbing member corrugate or crush in a shock-absorbing manner, as illustrated in FIG.  4 . 
     Thus, a head impact on the trim of  40  toward the body pillar will initially cause the outer shock-absorbing member  46  to move toward the body panel in a shock-absorbing manner, and then, upon contacting the rail, push the rail  22  toward the body pillar  12 . Thus initially the impact of the moving object striking the bolt end of the seat belt anchor will initially cushion the impact as it deforms the walls of the outer shock-absorbing member. The rail then crushes the walls of both shock-absorbing members. 
     It is to be understood that other forms of shock-absorbing members take other configurations but generally have deformable or crushable walls that are perpendicular to the body pillar, and deform upon a load applied to either the Bolt end of the anchor or as illustrated in an impact in direction of arrow  39 A in FIG. 2, or toward the rail components in the direction of arrow  39 B of FIG. 2. A variety of crushable shock-absorbing elements may be employed to function as the outer and lower shock-absorbing member, such as shock-absorber  60  illustrated in FIGS. 9 and 10. 
     FIGS. 11-13 illustrate another embodiment of the invention in which an inner shock-absorbing member  100  has a hollow, stepped conical configuration. Member  100  has a central opening  102  that fits snugly but slidably around bolt shank  28 . Member  100  has an uncollapsed height that fits tightly between the bottom of rail  22  and base wall  20 . Member  100  has three cylindrical sections  104 ,  106  and  108  connected by annular steps  110  and  112  that are parallel to base wall  20 . The seams between the steps and the cylindrical sections are beveled as at  114  and thinned on the inside as at  116 . 
     Member  100  is filled with a semi-viscous fluid  118 , such as silicon gel, energy-absorbing foam, partly mastic, grease, or an oil and silicon combination, or other similar materials. 
     A head impact on the bolt will cause member  100  to collapse or rupture in a controlled shock-absorbing manner as the rail moves toward pillar  12 .