U.S. patent application number 11/450114 was filed with the patent office on 2007-12-13 for exercise apparatus.
Invention is credited to Conrad R. Fuller.
Application Number | 20070287614 11/450114 |
Document ID | / |
Family ID | 38822662 |
Filed Date | 2007-12-13 |
United States Patent
Application |
20070287614 |
Kind Code |
A1 |
Fuller; Conrad R. |
December 13, 2007 |
Exercise apparatus
Abstract
An exercise apparatus comprising a rigid movable booster bar
having two flexible elastic elements attached to the booster with
an attachment. The attachments are spaced from each other and
configured to allow winding the elastic element upon the booster
bar by rotating the booster bar. Each flexible elastic element
comprises at least two stages of flexible shock cords, with the
stages disposed serially along the length of the flexible element,
with adjacent stages having a different elastic stiffness.
Inventors: |
Fuller; Conrad R.; (Salt
Lake City, UT) |
Correspondence
Address: |
JAMES SONNTAG;JAMES SONNTAG, PATENT ATTORNEY
P.O. BOX 9194
SALT LAKE CITY
UT
84109
US
|
Family ID: |
38822662 |
Appl. No.: |
11/450114 |
Filed: |
June 9, 2006 |
Current U.S.
Class: |
482/121 ;
482/123; 482/126 |
Current CPC
Class: |
A63B 21/28 20130101;
A63B 21/00069 20130101; A63B 21/1645 20130101; A63B 21/169
20151001; A63B 21/00185 20130101; A63B 21/00043 20130101; A63B
21/0552 20130101; A63B 21/0557 20130101; A63B 21/4001 20151001;
A63B 21/0555 20130101; A63B 2208/0204 20130101; A63B 21/0442
20130101; A63B 2071/027 20130101 |
Class at
Publication: |
482/121 ;
482/123; 482/126 |
International
Class: |
A63B 21/02 20060101
A63B021/02 |
Claims
1. An exercise apparatus comprising: a rigid movable booster bar;
two flexible elastic elements, each attached to the booster bar at
a near end with an attachment, the attachments spaced from each
other and configured to allow winding the elastic element upon the
booster bar by rotating the booster bar, to allow a gripping region
on the booster bar, each flexible elastic element comprising at
least two stages of flexible shock cords, with at least two stages
having a different stiffness, the stages attached to each other end
to end so that they are disposed serially along the length of the
flexible element, a distal end of each flexible element configured
for a moving or fixed attachment to allow stretching of the
flexible element.
2. An exercise apparatus as in claim 1 wherein the stages comprise
one or more flexible shock cords.
3. An exercise apparatus as in claim 2 wherein two stages with
different stiffness have a different number of shock cords.
4. An exercise apparatus as in claim 2 wherein two stages with
different stiffness comprise shock cord strands of a different
stiffness.
5. An exercise apparatus as in claim 1 wherein a distal end of each
flexible element is attached to a fixed object.
6. An exercise apparatus as in claim 1 wherein a distal end of each
flexible element is attached to an opposing member.
7. An exercise apparatus as in claim 6 wherein the opposing member
is movable.
8. An exercise apparatus as in claim 6 wherein the opposing member
is fixed.
9. An exercise apparatus as in claim 6 wherein the opposing member
is a flexible strap with the distal ends attached to either end of
the strap.
10. An exercise apparatus as in claim 9 wherein the flexible strap
is elastic or non-elastic.
11. An exercise apparatus as in claim 6 wherein the opposing member
is a nonflexible bar or platform.
12. An exercise apparatus as in claim 11 wherein the opposing
member is configured the same as the booster bar.
13. An exercise apparatus as in claim 1 wherein the stages are
attached to each other by one or more of knots, sewing, glue,
fusion, clamps, ties, tape wrapping, and molded structures.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] (Not applicable)
FEDERAL RESEARCH STATEMENT
[0002] (Not applicable)
BACKGROUND OF INVENTION
[0003] The use of exercise machines has proliferated in the last
decade or so. In general there are two main classifications of such
machines--those primarily intended for use in a commercial sports
center and those primarily intended for use in the home. Those
intended primarily for use in a sports center are quite complex,
are structurally heavy and bulky, are usually attached to the floor
or the wall, and oftentimes have a complicated arrangement of
levers, pulleys, weights, etc. Normally they may also be adjustable
for different users having different physical strengths. Those
intended primarily for the home are simpler, lighter, much less
expensive but still adjustable to some degree.
[0004] One such exercise machine comprises flexible elastic shock
cords, usually two, which are stretched by a force exerted by the
user. As a cord is stretched more and more, the force required to
stretch it increases more and more. One end of the shock cord is
attached to a fixed structure and the other end attached to a
booster bar adapted to be moved by the user's arms or legs as the
cord is stretched by the user. As a natural consequence of the size
of the user the stretched length of the shock cord will be
substantially constant for a given user but will be different for a
different user. Also as a natural consequence of the physical
characteristics of shock cords the force-length curve is an inverse
exponential when the force is displayed as the abscissa. Thus the
maximum force required for a given user to stretch his arms or his
legs to their fullest extent depends on the characteristics of the
shock cord and also on the ratio of the stretched length to the
unstretched length of the shock cords. Since a different user
having a different physical size or strength will require a
different ratio of stretched length to unstretched length it
becomes necessary to provide some means for shortening or
lengthening the unstretched length. This is normally effected by
means of clamps; however the clamps oftentimes damage the shock
cord and thus make the shock cord essentially unusable after a
given number of adjustments.
[0005] In U.S. Pat. No. 5,125,649, to Conrad Fuller (Fuller)
(incorporated hereby by reference) is an exercise machine with a
booster bar that mitigates the problems of adjustment found in
previous systems, where the stretched and unstretched length of the
shock cord are adjusted by the user without the use of clamps or
tools. In the Fuller system a booster bar is attached to pair of
flexible elastic shock cords, which have their other ends attached
to fixed structural members. The user exercises his arms or his
legs by repeatedly pushing against the booster bar, thus stretching
and unstretching the shock cords. The unstretched (and thus the
stretched) length of the shock cords is adjusted by rotating the
booster bar about its axis, thus winding or unwinding, the shock
cords around the booster bar. This, in turn, adjusts the force
required to stretch the shock cords to a given dimension.
[0006] However, the Fuller system is still not adequate in
providing an exercise machine that can be used by different users
of different size and with different strengths. This is due to the
force-length properties of braided shock cords, which as mentioned
in the Fuller patent can be represented as an inverse exponential
curve. Basically as the cord is stretched, the stretching or return
force is approximately constant or increases proportionally at a
modest rate. But, as the maximum stretching length for the cord is
approached, the return force increases much more rapidly, where (at
least as perceived by the user) even significant increases in the
force will not cause the cord to stretch further. Thus, the
perceived effect by the exerciser is a movement that is suddenly or
abruptly stopped. In other words, as the cord is stretched, the
user at first perceives a constant or modest increase in force as
determined by the stiffness of cord until a point is reached where
the stretching or return force increases rapidly with no or little
increase in the stretching length. At this point the exerciser
perceives an abrupt stop and cannot continue extending the
cord.
[0007] Basically, a braided shock cord will extend, depending on
the particular cord construction, up to 100% or more of its
unstretched length, until it reaches a this "abrupt stop" point
where under higher and higher forces it will stretch only a small
amount.
[0008] As described in the Fuller patent, the length of the shock
cords can be adjusted by wrapping them around the booster bar.
However, when fully unwound to lengthen stretching cord and allow
the user to stretch the cords a greater distance before reaching
the abrupt stop, the initial force and the force over the most of
the length of the stretching is also reduced, which reduces the
exercise effect. To increase the force and the exercise effect, the
stretched length of the shock cord can be shortened by wrapping the
cord around the booster bar. But if the stretching length is
shortened too much this will prevent the user from extending the
cord to the length required for the exercise. This is because the
user is attempting to stretch the shortened shock cord beyond its
design and the "abrupt stop" is encountered before the exercise
movement is completed.
[0009] A partial solution is to use shock cords of different
elastic, i.e., stiffness, properties. "Stiffness" or "stiff" is a
measure of the amount of elastic return force obtained for a given
amount of stretching. For a strong person, a machine with stiffer
cords is chosen so that the stretching force is high at the
beginning during the stretch. Because the cord does not have to be
shortened excessively, and the abrupt stop isn't reached during
exercise movements, the person is allowed to stretch to the desired
length for the exercise. A weak person could not use such a
machine, because, even when the cords are fully unwound to the full
length, the stretching force is too high, and he would only be able
to successfully accomplish few or none of the exercises. For the
weak person, a machine with less stiff or compliant shock cords
would be suitable. However, the strong person would not find this
machine suitable, because she would be able to extend the cords as
far as she can extend her limbs without feeling adequate increase
in the stretching force. Winding the cords around the booster bar
to increase the force, may result in insufficient stretching length
where the abrupt stop will likely be reached during routine
exercises. Exercises with long stretches then become difficult or
impossible.
[0010] In summary, the Fuller machine has the ability to change the
stretching length of the shock cord, which enables a person to vary
the stretching force and to do a variety of exercises, from short
stretches to long stretches. But, the advantage is not fully met if
the stiffness of the shock cords does not well match with a user's
size and strength. This is a particular problem as the user becomes
stronger over time, requiring the user to obtain a new machine or
rebuild the old one.
SUMMARY OF INVENTION
[0011] An aspect of the present invention is an exercise apparatus
comprising a rigid booster bar with two flexible elastic elements
attached to the booster with an attachment. The attachments are
spaced from each other and configured to allow winding the elastic
element upon the booster bar by rotating the booster bar. Each
flexible elastic element comprises at least two stages of flexible
shock cords, with the stages disposed serially along the length of
the flexible element, with adjacent stages having a different
elastic stiffness.
[0012] The present invention is an apparatus that improves upon the
Fuller machine by extending the range of user size and strength
that can be matched to a particular apparatus. Any one apparatus is
optimal for a wider range of user size and strength. The apparatus
of the present invention can be used like the Fuller machine, by
stretching and unstretching flexible elastic elements by means of a
booster bar, and the user can change the stretching length of the
elastic elements by wrapping same upon the booster bar. However,
the present apparatus has replaced the shock cords in Fuller
machine with improved flexible elastic elements that have a more
optimum force-length curve. In addition, the apparatus of the
present invention, because of its unique construction, can be used
in different ways.
[0013] The improved elastic elements can be wound and unwound upon
the booster bar to adjust force, but with a small or minimal amount
of winding required to obtain a higher stretching force. This
leaves a larger stretching length and lessens the probability that
the abrupt stop will be reached during an exercise movement. The
cord can be stretched to high stretching forces without
encountering an abrupt stop, even in exercises requiring high force
and a long stretch.
[0014] Not only is the abrupt stop essentially eliminated, but the
force-length profile is improved. During a stretch, higher forces
are obtained at a slower rate. In addition, the stretching force
encountered in an exercise movement is over a wider range, allowing
a user to start the stretch at a lower force and stretch up to and
sustain a higher force, a force that cannot be sustained if the
high force comes on quickly or abruptly. This allows a user to
sustain higher forces and gain more strength building benefit than
in previous devices. In previous devices, one could not gradually
obtain a high stretching force when starting a low stretching
force, because the abrupt stop would be reached before the high
force was obtained.
[0015] In addition, for any given apparatus a stronger user will be
able to derive more exercise and obtain and sustain higher forces,
and a weaker user has lower forces available that allows
accomplishment of more exercises. Both weaker and stronger users
benefit from the better force-length profile. Thus, it is possible
by practice of the invention that a single apparatus can be
provided that better meets the needs of a person as he grows
stronger, and be more easily adjusted for wider variety of people,
including children, adults, athletes, sedentary persons, and
persons with physical disabilities.
[0016] The apparatus of the present invention achieves the above
advantages in part by having a rigid booster bar with a flexible
elastic element constructed with multiple stages of braided elastic
stretch cords attached to each end. By "staged", is meant that the
length of each stretch cord is subdivided into at least two regions
or stages. Each stage is constructed with one or more braided shock
cords, such that each adjacent region has a different stiffness
from its neighboring or adjacent stages. Thus the stages are
attached in series end to end such that the stiffness of the
elastic element changes from stage to stage. This contrasts with
the Fuller machine where the elastic cords are designed with
essentially the same stiffness for their entire length.
[0017] Because the flexible elastic element is staged, with high
stretch force a high elongation can be obtained without
encountering an abrupt stop. This is in part to the fact that the
large stretching forces can be obtained with a minimum of wrapping
around the bar, allowing more of the length of the elastic element
to be stretched.
[0018] In addition, as the flexible element is stretched, the
lengthening or elongation is not distributed evenly along it
length. During a stretch all of the stages will begin to elongate,
but the less stiff stages will initially stretch more than the
stiffer stages. As the less stiff stages approach their maximum
elongation, more elongation will then occur in stiffer stages.
Thus, elongation is serially transferred from the less stiff stages
to the stiffer stages, with the stiffest stages being the last to
sustain significant elongation. The stiffest stage is designed to
sustain the maximum design force of the equipment without reaching
its maximum elongation required for exercise. Thus, at any
elongation during exercise, there are always one or more stages
that have not reached maximum elongation, thus eliminating an
abrupt stop.
[0019] Furthermore, at the beginning of the stretch the force is
mostly determined by the least stiff or most compliant stage, but
the elastic element can be stretched to a high final force as
determined by the stiffest stage. By the staged system a rather
even force profile can be provided that extends from a low
stretching force of stiffness to a stiffness, and this profile can
be predetermined by the selection of different stiffnesses of
multiple stages.
BRIEF DESCRIPTION OF DRAWINGS
[0020] FIG. 1 is a perspective drawing of an exemplary exercise
apparatus.
[0021] FIG. 2A to FIG. 2N are schematic drawings illustrating
various configuration of an exercise apparatus.
[0022] FIG. 3 is a drawing of part of an elastic element of an
exercise apparatus.
[0023] FIG. 4 is another drawing of part of an elastic element of
an exercise apparatus.
[0024] FIG. 5 is a perspective drawing of an exercise apparatus in
use.
DESCRIPTION
[0025] Reference is now made to FIG. 1, and FIGS. 2A to 2N. The
apparatus 11 comprises a booster bar 13 with two elastic element 15
attached to the booster bar 13 by an attachment 17. Each elastic
element comprises two or more stages 19, with at least two adjacent
stages having a different stiffness.
[0026] The stages are constructed of braided elastic cords 23, also
known as "shock cords", or "bungee cords". These cords have an
inner core of an elastomer, such as latex, covered with a braided
sheath. Shock cords are widely available in various diameters and
stiffness. Any diameter can be used. Diameters between 1/4 and 1/2
inches have been found suitable.
[0027] A stage may comprise one shock cord or multiple shock cords
attached together in parallel. Multiple shock cords in a stage may
be of the same stiffness and diameter or different stiffness and
diameter. In addition, the thickness and diameter of shock cords in
the different stages may be the same or different.
[0028] A requirement of the present invention is that the elastic
element comprise at least two adjacent stages that have a different
stiffness. The varying stiffness of the stages can be provided by
changing the number of shock cords in the stages. Thus, for
example, a first stage may comprise one shock cord, a second stage
or two shock cords, and third stage or three shock cords. The stage
may be in any order. It is preferred that the stage with fewer
shock cords be adjacent to the booster bar to ease the wrapping of
the elastic element around the bar easier. However, putting stiffer
stages adjacent the booster bar is also contemplated. In the table
below is shown various illustrative combinations, showing the
number of shock cord strands in each stage, with the first being at
the near end 18 nearest to the booster bar. Also in the Table,
there are references to Figures illustrating that particular
combination.
[0029] The stiffness can also changed by changing the stiffness of
the cords used in the stages. Thus, for example, a two-stage
flexible element can be constructed with 1/4 in. cord in stage 1,
and 1/2 inch cord in stage two. Referring to FIG. 2G and FIG. 2H
are shown flexible elements, each with a thicker or stiffer cord
(e.g. 1/2 in) continuing through all stages, with a less stiff or
thinner cords (e.g. 1/4 in) in stages 2 and 3. FIG. 2G shows one
thinner and one thicker in stage 2, while FIG. 2H shows two thinner
and a thicker cord in stage two. In stage three are respectively
two thinner and one thicker in FIG. 2G, and one thinner and two
thicker in FIG. 2H.
TABLE-US-00001 TABLE No. of Shock Parallel Cords in No. of
Respective Stages (Bold Nos. Figure Stages represent stiffer cords)
where illustrated. 3 1-3-4 FIG. 1 5 1-2-4-6-7 Not Shown- 4 2-1-2-3
Not Shown 2 1-3 FIG. 2A 2 1-2 FIG. 2B 3 1-2-3 FIG. 2C 3 1-3-5 FIG.
2D 3 1-2-3 FIG. 2E 3 2-3-4 FIG. 2F 3 1-(1, 1)-(2, 1) FIG. 2G 3
1-(2, 1)-(1, 2) FIG. 2H 4 1-2-4-6 FIG. 2I 3 3-1-5 FIG. 2J 3 2-1-3
FIG. 2K 3 1-3-1 FIG. 2L 5 1-3-5-3-1 Not Shown 3 2-2-3 FIG. 2M 3
1-1-1 FIG. 2N
[0030] There must be at least two stages having different stiffness
in an elastic element. The more stages, the more even will be
force-length profile, but the number of stages is limited by
practical construction limitations. More stages may be recommended
where there is a large difference between the number of cords
between the most compliant and the stiffest stage. The length of
the stages can be any suitable length. The stages may of the same
length or one stage may be lengthened or shortened relative to the
others.
[0031] Where there are three or more stages, stages may have the
same or different stiffness as long as there are at least two
stages that are adjacent and have different stiffness. Combined
length of the stages, or the total length of an elastic element is
consistent with the nature of the exercises to be performed, the
size of the user and the construction of the opposing element. For
an exercise device as in FIG. 1, a flexible elements of length
around 4 feet are suitable.
[0032] The stages are attached to each other end to end in series
by a suitable attachment system 21. Methods for attaching cords to
one another at the ends of the stages can be any suitable method,
and include any combination of: tying with knots, thermally fusing,
gluing, molding together without or with separate elements, sewing,
using crimped or other metal fasteners, wrapping or fixing material
around the cords (e.g., wire ties, tape, string, shrink-wrap,
wire). One or more shock cords can be continuous through adjacent
stages. For example, a single cord may extend through all of the
stages, or through two or more stages. (See FIGS. 2G and 2H).
[0033] FIG. 3 is a detail of a attachment 21 of stages of a
flexible element and shows how shows cords 23 can be assembled into
stages using knots 31 and polymeric wire ties 29. The figure also
shows attachment 27 of the last stage or the distal end of the
elastic element attached to an opposing member 25. In FIG. 3 the
illustrated stage has three cords joined to a stage of one cord.
One cord is continuous though both stages. The opposing member is a
flexible web strap and is attached using knots 31 and tape wrapping
.33
[0034] FIG. 4 is another detail of a flexible element showing a
stage of four cords 23 glued and bound with wrapping tape 33 at the
joinder with an adjacent stage of one cord. Also note in FIG. 4 is
a loop. The loop 35 can function as an opposing member, by, for
example, attachment to a foot, or fixed object. The loop can also
function as part of the attachment to an apposing member of any
suitable configuration.
[0035] The attachment to the booster bar may be the same as in the
Fuller machine. The attachment is preferably placed so that the
elastic elements can be wound upon a region of the booster bar
between the attachments, with handgrips outside of the attachments
at the ends of bar, as illustrated in FIG. 1, and FIG. 5. It is
preferred that the least stiff stage in the elastic element be at
its near end 18, i.e., the end that is near to or attached to the
booster bar. This is to ease the winding of the flexible element
around the bar. However, any of the stiffer stages can be the first
stage or the stage at the near end 18 that is attached to the
booster bar, as long as such does not materially affect the
function of the exercise apparatus. (See FIGS. 2J and 2K) In FIG. 5
are shown elastic elements 15 wrapped around the booster bar
13.
[0036] The near ends 18 of the elastic elements 15 are attached to
the booster bar 13, by a fixed attachment 17 to permit winding, so
that the stretched length of the elastic element can be adjusted by
rotating the booster bar and thus winding cords of the stages
around the booster bar to any degree desired. The attachment may
also optionally include a length of nonstretching flexible cord
between the cord and the booster bar.
[0037] Optionally, handgrips 37 (FIG. 1) are applied to the bar in
an appropriate region for grasping the bar, such at the ends of the
bar, or in a medial hand grip region. This is to assist the user in
grasping and holding the bar, to ease holding and winding of the
bar, and hinder rotation of the bar within the grasp while the
elastic elements are stretched. The grips may be any suitable
materials, such as sections of hoses of suitable diameter, shrink
wrap polymers, rubber applied by stretching or dipping, wrapped
plastic or cloth tape, and the like. However, it is also
contemplated that only a bare booster bar be used in apparatuses
where adequate gripping force can be applied by the bare hands or
with gloves.
[0038] The booster bar may be any suitable bar-like structure of
suitable strength and dimension that functions as described. The
bar may be solid or tubular, and may be of metal (aluminum, steel,
aluminum, etc.) wood, polymeric materials (fiber reinforced
polymers, engineering plastics, etc.) or any other suitable
material. The bar may a single unit, assembled from separate parts,
or may be constructed to allow disassembly into smaller parts for
transport. This may be by means of telescoping tubes or the like.
The cross-section is circular, or non-circular (oval, polygonal,
polygonal with rounded edges, ridged, knurled, etc.), but
sufficiently round to allow winding of the elastic members around
the booster bar.
[0039] The structure and placement of the opposing member and of
booster bar are such to work the elastic elements while performing
an exercise movement. The opposing member for an exercise can be
placed, for example, under one or both feet (FIG. 5), behind the
back, under a knee of a bent leg, or under the buttocks. In
addition, where an opposing member is a second apparatus of the
invention, or a second booster bar (FIG. 2N), or other suitable
structure, two people may exercise in tandem with one holding and
moving the booster bar 13, and the other holding and moving the
opposing member 25.
[0040] An opposing member may be any suitable structure, including
those illustrated herein, and the structures disclosed in Fuller,
U.S. Pat. No. 5,125,649. As an example, the opposing member 25 may
also be a flexible sling (FIG. 1). A flexible sling comprises a
flexible non-elastic or elastic strap or web of sufficient width
and length to be comfortable for the exercise contemplated for the
apparatus of the invention. The distal end 26 of the elastic
element 15 or opposing member 27 may also be attached to a fixed
object, such furniture, a wall or closed door, which functions as
or a part of an opposing member.
[0041] Any configuration of booster bar, elastic elements, opposing
member, and respective attachments are contemplated as long as the
booster bar and opposing member are held in a moving or fixed
positions to oppose each other in a stretching exercise movement.
For example, the booster bar can be held in the hands, with an
opposing member sling under a foot or feet (FIG. 5). For example,
booster can be placed over a shoulder, head, across the shoulders,
with a hand or hands holding bar to provide a nonmoving attachment
for stretching movement by a leg with its foot in the sling. In any
exercise, the user can wrap or unwrap the elastic element around
the bar, as required, to adjust the stretching length and adjust
the force. The opposing member can also be a nonflexible platform
with the elastic elements attached at its ends, similar in form to
a swing seat (FIG. 5), or have a construction similar to a booster
bar (FIG. 2L).
[0042] The shock cords are preferably seized, fused, taped, or the
like, at each end to prevent unraveling. The near ends of the
elastic elements are also preferably attached to the booster bar by
a system that guards against sharp edges or pressure points bearing
against the elastic elements which could cause chafing, which
provides positive configurations for preventing the shock cords
from pulling away from the booster bar regardless of the force
exerted by a user, for preventing relative circumferential movement
between the booster bar and the point of attachment of the shock
cords to the booster bar, and allowing a user to at least partially
wind the shock cords around the booster bar by rotating the booster
bar about its long axis.
[0043] An exemplary configuration comprises a booster bar which is
hollow, at least near its ends, with a hole near each end passing
through the wall. The near ends of the shock cords are threaded
through respective holes and out through the open ends of the
booster bar; providing a first knot at the near end of each shock
cord. Each shock cord is pulled back such that the first knot is
positioned inside the booster bar adjacent the hole; and a second
knot is tied in each shock cord at a position adjacent the booster
bar. As a variation, each shock cord, after having its first knot
pulled back inside the booster bar, is looped around the booster
bar, and passed under itself, thus providing the second knot.
[0044] An alternate method comprises utilizing a booster bar which
bar has a hole, near each end, passing completely through the bar;
threading the near ends of the shock cords through respective
holes; providing a first knot at the near end of each shock cord
adjacent the hole, and tying a second knot in each shock cord at a
position adjacent the booster bar. The same variation as noted
above may also be used in this configuration.
[0045] The distal ends 26 are attached to the opposing element by
any suitable method, and can comprise knots, loops, metal or
polymeric ties, rings or ties, sewing, wrapped tape, and the
like.
[0046] It is also contemplated for each elastic element to join
two, or more, elastic elements into a single elastic element. Such
a multiple flexible element would comprise multiple elements at
each end of the booster bar attached in a parallel arrangement.
[0047] While this invention has been described with reference to
certain specific embodiments and examples, it will be recognized by
those skilled in the art that many variations are possible without
departing from the scope and spirit of this invention, and that the
invention, as described by the claims, is intended to cover all
changes and modifications of the invention which do not depart from
the spirit of the invention
* * * * *