Rotatable seat belt buckle mounting bracket for a vehicle seat adjuster with a catcher bracket buckle brace

A track assembly for a vehicle includes an upper track slidably mounted in a lower track. A seat belt buckle mounting bracket is attached to the upper track and connects a fixed seat belt to the upper track. The seat belt buckle mounting bracket includes first and second angularly disposed legs, with the first leg attached to the upper track and the second leg attached to a fixed seat belt buckle. The attachment structure mounts the seat belt buckle mounting bracket in a first, normal operating position in which the second leg of the bracket extends upward from a side wall of the upper track. The attachment structure permits the seat belt buckle mounting bracket to rotate from the first position under a force applied through the fixed seat belt to a second position in which the second leg of the bracket is substantially aligned with the longitudinal axis of the upper track to place the first and second legs of the bracket in tension with the applied force. The second position provides a strong geometry position for the seat belt buckle mounting bracket. The attachment structure also includes a catcher strap connecting the seat belt buckle mounting bracket and upper track to the rear torsion bar or tube to increase the ultimate load before failure, and to transfer the load in a manner so that the load is shared between the buckle bracket and the rear torsion bar for subsequent transmission to the rear riser.

RELATED APPLICATIONS 
The present application is related to application Ser. No. 07/876,549 filed 
Apr. 30, 1992 entitled POWER SEAT ADJUSTER WITH DRIVE GEAR FORCE BYPASS by 
inventors Derek K. Gauger, Kirk K. Horvet and Phillip Chaban, now U.S. 
Pat. No. 5,316,258 and application Ser. No. 07/876,616 filed Apr. 30, 1992 
entitled ROTATABLE SEAT BELT BUCKLE MOUNTING BRACKET FOR VEHICLE SEAT 
ADJUSTER by inventors Derek K. Gauger, Stephen D. Crawford and Jeffrey D. 
Ineich, issued as U.S. Pat. No. 5,303,983 all of these applications were 
assignable, at the time the inventions were made, to a common assignee, 
namely ITT Corporation. 
FIELD OF THE INVENTION 
The present invention relates, in general, to vehicle seats, and, more 
specifically, to seat belt attachments to vehicle seat adjusters. 
BACKGROUND OF THE INVENTION 
Seat adjusters are used on the front seat(s) of automotive vehicles to 
provide selective horizontal fore and aft, vertical and/or recliner 
movements of the seat. Such seat adjusters carry an upper support frame 
which supports the seat bottom and sometimes the seat back of the vehicle 
seat. The upper support frame is mounted on first and second, spaced track 
assemblies, each formed of an upper track which is connected to the upper 
support frame and which is slidably mounted in a lower track anchored to 
the vehicle floor. In a power seat adjuster, a drive mechanism, typically 
formed of a bi-directional electric motor, is mounted between the track 
assemblies and rotates a pair of drive shafts extending outward from the 
motor to a gear assembly or box mounted on each upper track. In one 
arrangement, the gear box rotates a lead screw extending below each upper 
track. A drive block mounted to the lower track threadingly receives the 
lead screw to cause reciprocal movement of the upper track and the 
attached upper support frame upon selective energization of the drive 
motor. Other drive mechanisms may also be incorporated into the power seat 
adjuster to provide vertical movement of the seat frame as well as pivotal 
movement of the seat back with respect to the seat bottom. 
Although such seat adjusters provide easy fore and aft movement of the seat 
in the lower tracks, it is imperative that the seat remain in a fixed, 
stationary position during a collision, such as a frontal collision, in 
order to prevent injury to the passenger using the seat. As a result, the 
weight and size of the seat adjuster components are selected to provide a 
maximum amount of strength to resist any movement under the high impact 
forces transmitted to the seat through the seat belt during a vehicle 
collision. Thus, the individual tracks, the torsion tubes or bars 
typically extending between and interconnecting the spaced upper tracks 
into a rigid structure and the other components of the seat adjuster are 
made with stronger materials and greater thicknesses and dimensions to 
provide the requisite amount of strength. 
In current usage, a fixed seat belt buckle mounting bracket is mounted on 
the rear end of one of the movable upper tracks. The seat belt buckle 
mounting brackets typically have an L-shape and are fixedly attached to 
the upper track by welding or by fasteners. One leg of the bracket is 
attached directly to the upper track, while the second leg extends 
integrally from the first leg upward from the upper track. 
This arrangement provides a stiffener for the upper track as well as 
providing a retention device for attaching a fixed seat belt carrying a 
bracket which receives the tongue of a corresponding seat belt portion 
extendably and retractably mounted on a reel. 
However, due to the attachment of the seat belt buckle mounting bracket on 
the upper track, forward movement of the passenger during a frontal 
vehicle collision exerts a load on the seat belt which is transferred 
through the seat belt buckle mounting bracket to the upper track of the 
seat adjuster. This load creates a high stress at stress riser points 
formed at the compound bend in the seat belt buckle mounting bracket 
between the first and second legs of the bracket. Any tool marks, cracks, 
etc., at the bend, which typically is formed with a relief, are subject to 
fracture under such loads. 
Thus, it would be desirable to provide an upper track for a vehicle seat 
adjuster which has an improved seat belt buckle attachment means which 
overcomes the problems of previously devised seat belt buckle attachment 
means. It would also be desirable to provide an upper track of a seat 
adjuster having a seat belt buckle mounting bracket which is designed to 
change its geometry and/or position under load from a weak geometry 
position to a stronger geometry position. Furthermore, it would be 
desirable to provide a means for transferring load from the seat belt 
buckle attachment mounting bracket and upper track to the torsion bar 
assembly of the seat. It would also be desirable to gain higher loads 
during static loading, and greater reliability in the buckle system. In 
addition, it would be desirable to improve manufacturability by 
eliminating welds and reducing installation processing. 
SUMMARY OF THE INVENTION 
The present invention is a track assembly for a vehicle seat adjuster which 
has an improved seat belt buckle attachment means whose geometry changes 
under load to a strong, high strength geometry position to prevent 
fracture or breakage of the seat belt buckle attachment means and also 
transfers the load from the seat belt buckle attachment assembly and upper 
track to the torsion bar assembly. 
In a preferred embodiment, the track assembly includes a stationary lower 
track which is adapted to be anchored to the floor pan of a vehicle. An 
upper track is adapted to support a vehicle seat and is movably mounted on 
the lower track. Means are provided for adjusting the upper track relative 
to the lower track for fore and aft movement of the upper track in the 
lower track. Seat belt buckle attachment means are mounted on the upper 
track for attaching a fixed seat belt buckle to the upper track. 
The seat belt buckle attachment means includes a member having first and 
second angularly disposed legs. The second leg is adapted to be attached 
to a fixed seat belt buckle. Means are provided for fixedly attaching the 
first leg to the upper track in a first, normal operating position and for 
allowing rotation of the member to a second position relative to the upper 
track under a predetermined force imposed on the member through the seat 
belt buckle attached thereto to place the first and second legs of the 
member in tension. 
In a preferred embodiment, the seat belt buckle attachment means is an 
integral, one-piece member with the first and second legs being disposed 
at an obtuse angle with respect to each other. In the first, normal 
operating position, the second leg extends upward from the upper track and 
is disposed adjacent to a side wall of the upper track. In the second 
position, the second leg is disposed substantially co-axial with the 
longitudinal axis of the upper track to place the first and second legs of 
the member in tension which presents a stronger geometry position for the 
seat belt buckle mounting bracket and which has a higher strength to 
resist fracture, deformation, etc. 
A catcher bracket buckle brace means is provided to connect the seat belt 
buckle attachment means and upper track to the torsion bar or tube 
assembly. The catcher bracket buckle brace means preferably includes an 
elongated strap connected to the seat belt buckle attachment means and 
upper track at both ends and wrapped around the rear torsion bar 
intermediate the ends of the strap. During a frontal collision, the strap 
transfers load from the seat belt buckle attachment means and the upper 
track to the rear torsion bar assembly, thereby increasing the amount of 
load carried through the structure before failure. 
The seat belt buckle mounting bracket employed in a track assembly for a 
vehicle seat adjuster according to the present invention overcomes 
problems associated with previously devised seat belt buckle mounting 
brackets that are attached in a fixed and stationary manner to the movable 
upper track of a vehicle seat adjuster. By rotatably mounting the seat 
belt buckle mounting bracket to the upper track, the seat belt buckle 
mounting bracket can rotate under a load imposed on the seat belt buckle 
mounting bracket through the seat belt to a stronger geometry position 
which resists fracture or breakage and which insures that the seat belt 
buckle mounting bracket remains attached to the upper track of the track 
assembly during a frontal vehicle collision and despite any deformation or 
upward movement of the upper track with respect to the stationary and 
fixed lower track. In addition, the catcher bracket buckle brace means 
transfers the load effectively from the seat belt buckle mounting bracket 
and upper track to the rear torsion bar assembly for increased load 
capabilities during frontal vehicle collisions. 
Other objects, advantages and applications of the present invention will 
become apparent to those skilled in the art when the following description 
of the best mode contemplated for practicing the invention is read in 
conjunction with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawing, and to FIGS. 1 and 2 in particular, there is 
illustrated a seat adjuster 10 which variably positions an automotive 
vehicle seat in any user selected position. By way of illustration and not 
limitation, the seat adjuster 10 depicted is a power seat adjuster, and is 
a so-called "eight-way" adjuster providing horizontal fore/aft, vertical 
up and down movement of separate front and rear portions of the adjuster 
as well as pivotal tilting of the seat back with respect to the seat 
bottom. It will be understood, however, that the present invention 
described hereafter is employable with either a manual or a power seat 
adjuster which includes at least a horizontal fore/aft movement and any 
number of other movements. In addition, the catcher bracket buckle brace 
of the present invention can be employed on the inboard upper track 
assembly of either the driver's side, or the passenger's side, vehicle 
seat. 
As is conventional, the seat adjuster 10 supports a conventional vehicle 
seat, not shown, which includes a seat bottom and a seat back. An upper 
support frame is provided on the seat adjuster 10 for supporting and 
connecting the seat bottom and seat back to the seat adjuster 10. The 
upper support frame includes a pair of spaced, longitudinally extending 
frame members or rails 12 and 14. Mounting brackets 16 and 18, for 
example, are mounted on the ends of the frame members 12 and 14, 
respectively, and provide a mounting surface for connecting the seat 
bottom to the upper support frame. A pair of hinge plates 20 are also 
mounted on the upper support frame and provide a pivot connection between 
the seat back and seat bottom to permit selective tilting or pivotal 
movement of the seat back with respect to the seat bottom as is typical in 
so-called "seat recliners". 
Various drive assemblies are depicted mounted on the seat adjuster 10 to 
provide selective movement of the seat adjuster 10 along various axes. For 
example, front and rear vertical drive motors 22 and 24, respectively, are 
mounted on the seat adjuster 10 and connected to conventional lead screws 
and drive blocks or nuts to move front and rear portions of the vehicle 
seat to provide selective vertical adjustment of the front and rear 
portions of the vehicle seat. In addition, a recliner drive motor 26 is 
interconnected by a pair of rotatable drive shafts 28 to gear boxes 30 
which are each coupled to a lead screw 32. The lead screws 32 are 
connected to one of the pivotal seat back hinge plates 20 mounted on 
opposite sides of the seat adjuster 10 to provide selective pivotal 
adjustment of the seat back with respect to the seat bottom. 
A horizontal drive means formed of a bi-directional electric motor 34 which 
is fixedly mounted to one of the upper tracks 52 by means of a suitable 
bracket 38. A pair of rotatable output shafts 40 extend outward from the 
horizontal drive motor 34 to a rotatable connection with a lead screw by a 
gear means mounted in opposed track assemblies as described hereafter. The 
output shafts 40 are, in an exemplary embodiment, flexible steel shafts 
covered by a polyurethane sleeve. 
The seat adjuster 10 also includes a rear torsion bar or member 42 and a 
front torsion bar or member 44. This pair of tubular torsion bars or 
members 42 and 44 extend between and are connected to the opposed track 
assemblies 46 and 48 and provide a rigid support structure for the seat 
adjuster 10. As each of the track assemblies 46 and 48 is identically 
constructed, the following description will refer to only one track 
assembly 48. It will be understood that the opposite track assembly 46 is 
constructed in the same manner. 
Referring now to FIGS. 1 and 2, and in detail to FIGS. 3 and 4, the track 
assembly 48 includes a lower track 50 and an upper track 52 which is 
slidably disposed within the lower track 50 and reciprocally movable 
bi-directionally along the lower track 50 under the control of the 
horizontal drive means 34. The lower track 50 is formed of an integral, 
one-piece member having a substantially planar central wall or web 54 and 
a pair of identically formed side walls 56 and 58 extending from opposite 
sides of the central wall 54. Each of the side walls 56 and 58 includes a 
vertically extending, outer side wall 60, a top wall 62 and an inward 
disposed lip or wall 64 which extends substantially vertically downward 
from the top wall 62 and is spaced from the outer side wall 60. The outer 
side wall 60, the top wall 62 and the inner wall 64 are formed in an 
inverted J-shape creating and surrounding a longitudinal extending channel 
72. The lower edge of the inner wall 64 is spaced from the central wall 54 
of the lower track 50 to define a longitudinally extending slot 
therebetween as denoted by reference number 66. 
A plurality of spaced apertures 68 are formed in the outer side walls 60 of 
each side wall 56 and 58. A slide member or sleeve 70, only one of which 
is shown in FIG. 3, is mounted in each channel 72 formed by the spaced 
portions of the central wall 54, the outer side wall 60, the top wall 62 
and the inner wall 64 on opposite sides of the lower track 50. The slide 
or sleeve 70 is substantially C-shaped and is complimentary to the shape 
of the channel 72. The sleeve 70 is formed of a suitable plastic material 
to provide a smooth sliding surface for the upper track 52, described 
hereafter, which is slidingly disposed within the slide or sleeve 70. A 
plurality of outwardly extending pins 74 are formed on and extend outward 
from a side wall of the slide or sleeve 70 and engage the apertures 68 in 
the outer side wall 60 of the corresponding side walls 56 and 58 of the 
lower track 50 to securely and position the slide or sleeve 70 in a 
stationary manner within the lower track 50. 
As shown in FIG. 2, a front riser 80 and a rear riser 82 are attached to 
the lower track 50 at opposite ends thereof and provide a mounting 
connection to the vehicle floor by means of bolts or other suitable 
fasteners or anchors. 
As shown in detail in FIG. 3, the upper track 52 is in the form of an 
elongated, one-piece, integrally formed member which is stamped, extruded, 
or otherwise formed from a suitable material, such as a high-strength, low 
alloy steel. 
All of the various portions described hereafter which form a part of the 
upper track 52 are integrally formed with the entire upper track 52 and 
form an integral, continuous, unbroken, non-separate, part of the complete 
upper track 52. The upper track 52 includes a first end 84 and an opposed 
second end 86. A raised central portion or surface 88 extends between the 
first and second ends 84 and 86. The side walls of the upper track 52 are 
formed in a channel-like configuration complimentary to the shape of the 
channels 72 in the lower track 50 so as to enable the upper track 52 to be 
slidably disposed within the lower track 50 in sliding contact with the 
sleeves 70. Thus, each side wall of the upper track 52 is formed with a 
substantially J-shaped channel configuration formed of an outer side wall 
90, a lower bottom wall 92 and an inner side wall 94 which extends to the 
central raised portion 88. The same channel-like configuration is also 
provided for the opposite longitudinal side wall of the upper track 52. 
During the formation of the upper track 52, which is preferably by a 
stamping operation, a pair of overlapping flanges 96 and 98 are formed at 
the second end 86 of the upper track 52. Aligned apertures 100 are formed 
in each of the flanges 96 and 98 and provide a mounting point for the 
attachment of a seat belt buckle bracket 102 to the second end 86 of the 
upper track 52. The seat belt buckle bracket 102 provides an attachment 
point for a conventional seat belt buckle, not shown. 
A first pair 104 of mounting flanges including spaced mounting flanges 106 
and 108 are integrally formed in the upper track 52 adjacent the first end 
84 thereof. A second pair 110 of mounting flanges including first and 
second mounting flanges 112 and 114 are integrally formed in the upper 
track 52 adjacent the overlapped flanges 96 and 98 at the second end 86 of 
the upper track 52. Each of the pairs 104 and 110 of mounting flanges is 
cut, such as by stamping, from the same material sheet used to form the 
entire one-piece upper track 52. After piercing, each pair of flanges 104 
and 110 are then bent outwardly from the raised central portion 88 of the 
upper track 52 so as to be disposed in a substantially vertically 
extending position when the upper track 52 is mounted in its operating 
position in the seat adjuster 10. Each of the mounting flanges 106, 108, 
112 and 114 forming the first and second pair of mounting flanges 104 and 
110 is substantially identically constructed with the exception of the 
mounting flange 106 which has an elongated end portion 116. An enlarged 
aperture 118 is formed in the end portion 116 to enable the drive shaft 40 
of the horizontal drive motor 34 to pass therethrough to its connection to 
the horizontal gear means, as described hereafter. 
A pair of co-axial aligned apertures 120 are formed in the mounting flanges 
106 and 108 of the first pair of mounting flanges 104. The apertures 120 
are preferably formed by an extrusion process which creates an inwardly 
extending, annular collar 122 extending toward the opposed mounting flange 
106 or 108. The aligned apertures 120 provide a mounting connection for 
the front tubular torsion bar 44 to the upper track 52 as described 
hereafter. 
Similar coaxial apertures 124 are formed in the mounting flanges 112 and 
114 of the second pair of mounting flanges 110 and are each formed with 
inwardly facing annular collars 126. The mounting apertures 124 provide a 
mounting connection for the other tubular torsion tube 42 as described 
hereafter. 
Additionally, a plurality of longitudinally spaced apertures, each having 
an outwardly extending, annular collar 128 are formed on the raised 
central portion 88 of the upper track 52 and provide a mounting connection 
for a bracket used to attach the vertical drive motors 22 or 24 to each 
upper track 52. 
As shown in FIG. 4, each torsion bar or tube, such as rear torsion tube 42, 
extends through the aligned apertures in the mounting flanges 112 and 114 
and the annular collars 126 associated therewith to connect the torsion 
tube 42 to the upper track 52. A fastener 130, such as a conventional push 
nut, is mounted on the outer end of the torsion tube 42 to securely attach 
the torsion tube 42 to the mounting flange 114. Referring briefly to FIG. 
1, each torsion tube, such as front torsion tube 44 is welded to a drive 
link 132 which is attached to the upper support, such as mounting bracket 
16 or 18, and spaced from the side wall of the upper track 52. 
Referring now to FIGS. 5 and 6, there is depicted a detailed illustration 
of a portion of the horizontal drive means which moves the upper track 52 
in either direction along the lower track 50. A gear means or box denoted 
generally by reference number 140 is mounted beneath the central raised 
portion 88 of the upper track 52 adjacent the first end 84 of the upper 
track 52. The gear box 140 includes a lightweight plastic housing 142 
which surrounds internal gears which translate rotation of the horizontal 
drive motor drive shaft 40 to rotation of the perpendicularly oriented 
horizontal lead screw 144. By way of example only, a worm 148 and a worm 
gear 152 are mounted within the housing 142 of the gear box 140. A 
substantially square slot 146 is formed in the worm 148 and receives one 
end of the horizontal drive motor output shaft 40. The worm 148 meshingly 
engages a helix thread 150 formed on the worm gear 152 mounted on one end 
of the lead screw 144. The worm gear 152 is preferably insert molded about 
a knurled end portion of the lead screw 144 as shown in FIG. 6. A metallic 
washer 154 is welded to the end portion of the lead screw 144 within the 
worm gear 152 to provide additional strength to the gear box 140, for 
reasons which will become more apparent hereafter. The worm 148 and the 
worm gear 152 are preferably formed of a high strength plastic, such as 
DELRIN.TM. or NYLON.TM.. 
A mounting pin 156 shown in FIG. 5 extends through a bore 158 in the 
housing 142 and engages opposed side walls 94 of the upper track 52 to 
mount the gear box 140 to the upper track 52. 
As shown in FIG. 2, the lead screw 144 threadingly engages a drive block 
160 which is mounted to the lower track 50 in a stationary manner by means 
of a screw or other fastener 162. In this manner, rotation of the lead 
screw 144 in either direction will result in a linear movement of the 
upper track 52 with respect to the stationary lower track 50 through the 
coupling between the lead screw 144 and the drive block 160. 
Referring again to FIG. 5, in another embodiment of the present invention, 
means are provided for bypassing the gear box 140 and transmitting forces 
imposed on the upper track 52 around the gear box 140 to the lower track 
50. The force transmitting bypass means 170 preferably is in the form of a 
front catcher strap or bracket which may have any suitable shape besides 
that illustrated in FIG. 5 and described hereafter. The shape of the front 
catcher strap 170 may be varied to provide a predetermined force versus 
load compliance characteristic such that the front catcher strap 170 
exhibits controlled elongation under force loading. The front catcher 
strap 170 is preferably in the form of a thin, planar strip formed to the 
desired shape. The front catcher strap 170 is also, preferably, formed of 
a mild steel. 
By way of example only, the front catcher strap 170, as shown in FIG. 5, is 
formed of an integral, one-piece member having first and second ends 172 
and 174 bent or formed into an overlapping position substantially in 
registry with each other. Each of the first and second ends 172 and 174 is 
identically constructed and has an enlarged, substantially annular shape 
with a centrally located aperture 176 formed therein. A substantially 
planar, angularly disposed bent portion 178 extends continuously from the 
first end portion 172 to a horizontally oriented planar portion 180. The 
front catcher strap 170 loops in an arcuate, loop-shaped portion 182 about 
the front torsion tube 44 extending through the first end 84 of the upper 
track 52. The arcuate, loop-shaped portion 182 may or may not be in 
contact with the front torsion tube 44. Extending from the arcuate, 
loop-shaped portion 182 is a second substantially linear portion 184 which 
merges into an angularly disposed, substantially planar portion 186 
disposed adjacent to the angularly disposed bent portion 178. The 
angularly disposed, planar portion 186 merges integrally into the enlarged 
second end portion 174. 
In normal operation of the seat adjuster 10, the front catcher strap 170 
merely rests in an inoperative position around the front torsion tube 44 
and over the gear box housing 142. The enlarged first and second end 
portions 172 and 174 surround the lead screw 144, with the lead screw 144 
extending through the apertures 176 in the first and second ends 172 and 
174 of the front catcher strap 170 without impediment. 
It will be noted that a similar front catcher strap 170 could be mounted 
around the gear box housing 142 on the front end 84 of the opposite track 
assembly of the seat adjuster 10, if a seat belt strap dispensing mount is 
desired on the opposite track assembly. 
In low load situations, such as those resulting from low or slow speed 
collisions of the vehicle having the seat adjuster 10 mounted therein, the 
bypass means or front catcher strap 170 on each track assembly remains in 
a substantially inoperative condition. During such low load situations, a 
force will be imparted by the seat belt buckle to the seat belt buckle 
attachment bracket 102 mounted at the rear end 86 of the upper track 52 of 
one of the track assemblies. This load is then transferred through the 
seat belt buckle bracket 102 to the upper track 52 and then along the 
upper track 52 to the gear box housing 142 by the mounting pin 156 
attached to the upper track 52. Although the gear box housing 142 is 
formed of a plastic material, under low load conditions, the gear box 
housing 142 will remain intact and thereby transmit the load through the 
worm gear 152 mounted therein to the lead screw 144. From the lead screw 
144, the load is transferred through the drive block 160 to the lower 
track 50 which is securely anchored to the vehicle floor by means of the 
front and rear risers 80 and 82. 
The force transmitting bypass means or front catcher strap 170 comes into 
operation during high load conditions which occur during high speed 
vehicle collisions. During such high load conditions, the loading is 
initially the same as that described above in that a force or load will be 
imparted through the seat belt buckle attachment bracket 102 to the upper 
track 52. The load is then transferred from the upper track 52 through the 
mounting pin 156 to the gear box housing 142. However, the high force or 
load will exceed the strength of the gear box housing 142 thereby 
fracturing the gear box housing 142. At the same time, during such high 
load conditions, the upper track 52 is moved forward toward the front of 
the vehicle which imparts an elongation or tension load on the front 
catcher strap 170. This brings the angular portions 178 and 186 of the 
front catcher strap 170 into contact with the upper portion of the gear 
box housing 142 thereby causing an elongation of the front catcher strap 
170 and a controlled straightening of the angular portions 178 and 186 of 
the front catcher strap 170. 
Even though the gear box housing 142 is fractured and unable to transmit 
the load therethrough, the washer 154 which is welded to the end of the 
lead screw 144 and insert molded within the worm gear 152 remains intact 
and transfers the load imparted by the first and second ends, 172 and 174 
respectively, of the front catcher strap 170 to the lead screw 144 where 
it is again transmitted through the drive block 160 to the lower track 50 
which is securely anchored to the vehicle floor. In this manner, the 
forces imparted on the seat adjuster 10 during low and high speed 
collisions are effectively transmitted through the various components of 
the seat adjuster 10 to the vehicle floor to prevent any undesirable 
movement of the seat adjuster 10 and the seat attached thereto during a 
collision. In the particular situation of a high speed collision which 
generates high impact forces on the seat adjuster 10, the front catcher 
strap 170 provides a force transmitting bypass path around the plastic 
gear box housing 142 which will fracture at a certain load and still 
enable the load to be transferred through the lead screw 144 and drive 
block 160 to the lower track 50 anchored to the vehicle floor. 
Referring again to FIGS. 2 and 3, in current vehicle seat adjusters, such 
as the vehicle seat adjuster 10, the seat belt buckle mounting bracket 102 
is mounted on one of the upper tracks 52 of the first and second track 
assemblies of the seat adjuster 10 and is movable therewith relative to 
the stationary lower track 50. 
The seat belt buckle bracket mounting 102 is typically formed of a high 
strength metal and, preferably, has an integral, one-piece construction. 
The seat belt buckle mounting bracket 102, in an exemplary embodiment, 
includes a first leg 200 and an angularly disposed second leg 202. The 
second leg 202 is typically disposed at an obtuse angle with respect to 
the first leg to present a suitable mounting surface for a fixed seat belt 
shown generally by reference number 204 in FIG. 3. As is conventional, the 
fixed seat belt 204 includes a short fixed belt portion 206 which may be 
mounted in a protective plastic sleeve 208. A seat belt buckle 210 is 
connected to an outer end of the fixed seat belt 206 and includes a socket 
212 for receiving the tongue, not shown, of an extendable/retractable belt 
portion of the seat belt system employed in a vehicle. One end of the 
fixed seat belt 206 and the fixed seat belt housing or sleeve 208 is 
provided with a through bore 214 which rotatably engages and is retained 
on an outwardly extending collar 216 formed on the upper end of the second 
leg 202 of the seat belt buckle mounting bracket 102. 
In FIG. 3, the seat belt buckle mounting bracket 102 is shown in a first, 
normal mounting position for normal use of the seat adjuster 10 during 
operation of the vehicle. In the first, normal position, the second leg 
202 extends upward from the upper track 52 and is located adjacent to the 
side wall 94 of the upper track 52. The first leg 200 is attached to the 
upper track 52 by means of a suitable fastener 218 which provides the dual 
function of fixedly maintaining the seat belt buckle mounting bracket 102 
in the first, normal position and, also, allowing the seat belt buckle 
mounting bracket 102 to rotate under a force or load applied to the seat 
belt buckle mounting bracket 102 during a frontal collision to a second, 
stronger geometry position as described hereafter. 
During the initial application of a load to the seat belt buckle bracket 
102, as shown in FIG. 3, the seat belt buckle bracket 102 will initially 
rotate in the direction of arrow 219 toward the first end 84 of the upper 
track 52. However, the continued application of load through the fixed 
seat belt 204 to the seat belt buckle mounting bracket 102 will result in 
an opposite, clockwise rotation of the seat belt buckle mounting bracket 
102 with respect to the upper track 52 toward the second end 86 of the 
upper track 52. Simultaneously, as such force or load increases, the rear 
end 86 of the upper track 52 will curl upward, as shown in FIG. 7, away 
from its normal, substantially planar, horizontal position. This curling 
of the second end 86 of the upper track 52 occurs simultaneously with the 
clockwise rotation of the seat belt buckle mounting bracket 102 until the 
seat belt buckle mounting bracket 102 assumes the second position shown in 
FIG. 7 in which the second leg 202 is substantially aligned with the 
longitudinal axis of the upper track 52. This second position is a 
stronger geometry position for the seat belt buckle mounting bracket 102 
since the first and second legs 200 and 202, respectively, are positioned 
to receive a tensile force applied through the fixed seat belt 204 to the 
seat belt buckle mounting bracket 102. 
The continued application of increasing force to the seat adjuster 10 will 
cause a further curling or upward movement of the second end 86 of the 
upper track 52 with respect to the associated lower track 50 as shown in 
FIG. 8. This upward curling is accompanied with deformation of the upper 
track 52 and an increase in the angle between the first leg 200 and the 
second leg 202 of the seat belt buckle mounting bracket 102 due to the 
tensile force applied to the bracket 102. However, as this is a stronger 
geometry position, the seat belt buckle mounting bracket 102 remains 
integrally affixed to the upper track 52 to prevent separation or fracture 
of the bracket 102 from the upper track 52. 
The attachment means 218 which provides such fixed attachment of the seat 
belt buckle mounting bracket 102 in a first, normal position and which 
also allows the seat belt buckle mounting bracket 102 to rotate to the 
second position shown in FIGS. 7 and 8, is formed, in a preferred 
embodiment, by a rivet which is mounted through aligned apertures formed 
in the first leg 200 of the seat belt buckle mounting bracket 102 and 
corresponding apertures formed in the overlapped flanges 96 and 98 at the 
second end 86 of the upper track 52. The rivet 218 allows such rotation of 
the seat belt buckle mounting bracket 102, as described above, yet retains 
the seat belt buckle mounting bracket firmly attached to the upper track 
52. 
Referring now to FIGS. 1-4 and 7-9, and specifically FIG. 9, catcher 
bracket means 220 is provided for transferring at least a portion of the 
load from the seat belt buckle mounting bracket 102 to the rear torsion 
member 42 thereby strengthening the attachment structure and transmitting 
forces imposed on the upper track 52 to the lower track 50. The catcher 
bracket means 220 preferably is in the form of a rear catcher strap or 
bracket 222 which may have any suitable shape besides that illustrated in 
FIG. 9 and described hereafter. The shape of the rear catcher strap 222 
may be varied to provide a predetermined force versus load compliance 
characteristic such that the rear catcher strap 222 exhibits controlled 
elongation under force loading. The rear catcher strap 222 is preferably 
in the form of a thin, planar strip formed to the desired shape. The rear 
catcher strap 222 is also, preferably, formed of a mild steel. 
By way of example only, the rear catcher strap 222, as shown in FIG. 9, is 
formed of an integral, one-piece member having first and second ends, 224 
and 226 respectively, bent or formed into an overlapping position 
substantially in registry with each other. Each of the first and second 
ends, 224 and 226 respectively, is identically constructed and has a 
centrally located aperture 228 formed therein. A first, substantially 
planar, portion 230 extends continuously from the first end 224 to an 
arcuate, generally bent-over or looped-shaped portion 232 adapted to 
substantially encircle the rear torsion member 42 extending through the 
second end 86 of the upper track 52. The bent-over, looped portion 232 
extends continuously and integrally from the first portion 230 to a 
second, substantially planar, portion 234. The second portion 234 extends 
continuously to the second end 226 and is generally in registry with the 
first planar portion 230. The arcuate, loop-shaped portion 232 of the rear 
catcher strap 222 may or may not be in contact with the rear torsion 
member 42. In normal operation of the seat adjuster 10, the rear catcher 
strap 222 merely rests in an inoperative position around the rear torsion 
tube 42. It should be noted that a similar rear catcher strap 222 could be 
mounted around the rear torsion bar 42 on the second end 86 of the 
opposite track assembly of the seat adjuster 10, if a seat belt strap 
dispensing mount is desired connected to the upper track of the opposite 
track assembly. 
In low load situations, such as those resulting from low or slow speed 
collisions of the vehicle having a seat adjuster 10 mounted therein, the 
rear catcher strap remains in a substantially inoperative condition. 
During such low load situations, a force will be imparted by the seat belt 
buckle to the seat belt buckle attachment bracket 102 mounted at the rear 
end 86 of the upper track 52 of at least one of the track assemblies. This 
load is then transferred through the seat belt buckle bracket 102 to the 
upper track 52 and then along the upper track 52 to the gear box housing 
142 by the mounting pin 156 attached to the upper track 52. The load is 
then transferred to the lower track 50 which is securely anchored to the 
vehicle floor by means of the front and rear risers, 80 and 82 
respectively. 
During high load conditions such as occur during high speed vehicle 
collisions, the rear catcher bracket means 220 comes into operation. 
During such high load conditions, the loading is initially the same as 
that described above in that a force or load will be imparted through the 
seat belt buckle attachment bracket 102 to the upper track 52. The high 
load will eventually exceed the strength of the upper track, and the upper 
track will bend upward as shown in FIGS. 2 and 3. The rear catcher strap 
222 will then transfer at least a portion of the load from the seat belt 
buckle bracket 102 to the rear torsion member 42, thereby increasing the 
ultimate load that can be carried by the structure before failure occurs. 
If the rear catcher means 220 is used in combination with the rotatable 
seat belt buckle bracket 102 described above and subjected to high load 
conditions, the rotatable seat belt buckle bracket 102 would initially be 
in the first position until the initial application of load rotates the 
bracket 102 into the second, stronger geometry position as described 
above. As additional load is applied to the bracket 102, the high load 
will eventually exceed the strength of the upper track 52, and the upper 
track 52 will bend upward as shown in FIGS. 2 and 3. The rear catcher 
strap 222 will then transfer at least a portion of the load from the seat 
belt buckle bracket 102 to the rear torsion member 42, thereby increasing 
the ultimate load that can be carried by the assembly before failure 
occurs. 
If the rear catcher means 220 is used in combination with the rotatable 
seat belt bracket 102 and/or the front catcher strap 170, and a high load 
is imposed to the assembly, the load will be transferred as described 
above with the additional benefit of the rear catcher strap 222 
transferring at least a portion of the load from the bracket 102 to the 
torsion member 42, thereby increasing the ultimate load that can be 
carried by the assembly before failure occurs. 
In summary, the rear catcher strap 222 or catcher bracket buckle brace 
permits higher loads during static loading and greater reliability in the 
buckle system. The manufacturing process is improved by eliminating the 
problems with welds previously used on the seat belt buckle bracket 102. 
Common problems with welds included no welds, cold welds, missing welds, 
incomplete welds and blow through weld Splatter, all of which had adverse 
impacts on the ultimate strength of the assembly. Eliminating welds also 
reduces the installation processing time, by reducing part handling during 
the required welding operations. The use of the rear catcher strap 222 in 
place of the welded plate for the seat belt buckle bracket, allows the 
force to be shared with the rear torsion bar 42, thereby increasing the 
load capable of being carried by the assembly before failure. The rear 
catcher strap 222 of the present invention preferably is used with the 
rotatable seat belt buckle bracket 102, sometimes referred to as a "swivel 
type" buckle bracket, in a power seat adjustor assembly, preferably 
including the front catcher strap 170 around the gear box housing as 
described above. 
The rear catcher strap 222 is mounted so that the inboard side of the rear 
torsion bar 42 slips through the loop-shaped portion 232. The mounted ends 
224, 226 of the rear catcher strap 222 rest on top of the folded over 
flanges 96, 98 of the upper track 52. The mounted ends 224, 226 are 
preferably interposed on top of the flanges 96, 98 and between the upper 
track 52 and the buckle bracket 102. The tendant of the buckle bracket 
rivet 218 slips through the buckle bracket 102, through the catcher strap 
apertures 228 and finally through the upper track 52. The end of the rivet 
tendant can then be upset by means of orbital forming. During forward 
loading of the track assembly, the upper track 52 deflects upward causing 
the catcher strap 222 to be in tension between the buckle bracket 102 and 
the rear torsion bar 42. This prevents the upper track 52 from taking all 
of the load by sharing it with the rear torsion bar 42. The end result is 
higher ultimate loads for the assembly and a change in failure mode from 
the buckle bracket 102 to the rear riser 82. 
While the invention has been described in connection with what is presently 
considered to be the most practical and preferred embodiment, it is to be 
understood that the invention is not to be limited to the disclosed 
embodiments but, on the contrary, is intended to cover various 
modifications and equivalent arrangements included within the spirit and 
scope of the appended claims, which scope is to be accorded the broadest 
interpretation so as to encompass all such modifications and equivalent 
structures as is permitted under the law.