Note: Descriptions are shown in the official language in which they were submitted.
_CKGROUND OF ~HE NVENT:[ON
The present invention relates generally to athletic
equipment and relates specifically to a leg stretching ap-
paratus.
Danc~rs, gymnasts, marshal arts practitioners, and
others are oftentimes called upon to perform an exercise
which involves the spreading apart of one's legs into a
so-called "split" positio~, in which the person's torso is
either sitting or reclining and the legs are pointing at
essentially right angles to the torso and 180 degrees with
xespect to each other. This maneuver requires a great deal
of flexibility which is generally achieved through various
stretching exercises. Oftentime, such exercises utilize
the individual's body weight to force the legs into a
proyressively wider stance. It is very difficult to control
the application of force when using one's body weight while
relaxing the muscles to be stretched at ,the same time.
Consequently, many people over-stretch the muscles actually
tearing muscles and ligaments, causing,at a minimum, very
painful injuries.
In the past, various types of leg stretching devices
have been used. In marshal arts training, it is desirable
to be able to extend one's leg over one's head in a kick.
Various devices are currently marketed which utilize a strap
located around the individual's foot and connected to a cable
going to a pulley located above the individual. Pulling on
the cable will stretch the individual's foot at progressive-
ly greater distances above the ground. Obviously, the
trainee must maintain his balance standing on one foot
while at the same time attempting to relax the leg muscles
and also pull on the rope raising the leg. Obviously, this
presents the expected problems and also serves to apply
substantial pressure to the trainee's knee joint with possi-
ble ~amage thereto.
Another device currently on the market permits the
operator to sit on the device with each leg being independent-
ly supported. The leg supporting devices are pivotally
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attached to the central portion of the machine upon which
the individual is seated. Cables extend from the outer por-
tion of the leg supporting devices through pulleys at the
rear of the machine and from there forward to a crank and
drum assembly. As the crank is wound the cab~es are
tightened, pulling the leg supporting members towards the
rear of the machine, forcing the user's legs into a "split"
position. There are numerous disadvantages with this type
of machine, however. Because of the location of the pulley
and cable arrangement extending to the rear of the machine,
the legs cannot be conveniently folded into the body of the
machine to provide a compact storage position. Additionally,
from both a safety and aesthetic viewpoint, it is desirable
to eliminate exposed cables connecting the leg supports to
the rear of the frame. Finally, and most importantly, the
prior art device depends upon hand cranking the winch
assembly to provide adjustments in the stretch force applied
to the legs. Thus, only relatively large-scale adjustment5
can be made, even when the near maximum muscle stretch
position has been obtained. Thus, the risk of injury from
such a device is comparatively high.
_MMARY OF THE INVENTION
Therefore, in view of the above and other disadvan-
tages of prior art leg stretching apparatuses, it is an
object of the present invention to provide a leg stretching
apparatus in which all cables are concealed wi~hin the base
and/or crank assembly of the device.
It is a further object of the present invention to
provide a leg stretching apparatus in which pulleys
previously located at the rear portion of the base can be
eliminated, allowing leg support members to be folded into
the base for compact storage.
An additional object of the present invention is to
provide a leg stretching apparatus utilizing a crank
assembly for providing large-scale stretching movement of
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leg supports and to pxovide a further apparatus for applying
minute and contolled stretching movements to the leg sup-
ports once the near maximum muscle stretch position has been
reached.
It is an additional object of the present invention to
provide a leg stretching apparatus which not only supports
the entire leg while undergoing stretching, but also can be
fol~ed into a relatively compact assembly which can be
easily transported.
It is an additional object of the present invention to
provide a collapsible leg stretching apparatus in which any
cables present are concealed within the base and crank
assembly of the device and which is capable of applyiny
minute and controllea rotational forces to the operator's
legs at least when a near maximum muscle stretch position
has been reached.
The above and other objects are achieved in accordance
with the present invention by providing.a torso restraining
member in the form of a seat and pivotally mounting two leg
supporting members thereto. Each of the leg supports in a
preferred embodiment has a disk segment attached thereto
with a groove in the outer periphery thereof. A cable is
attached to the disk such that when the cable is pulled
towards the forward direction (away from the user), the leg
support is pivoted rearward towards the "split" position.
In a preferred embodiment, the torso restraining member
conceals the cable and disk assembly from view.
The cables from each disk assembly pass ~hrough a
guide and go up to a conventional crank and drum assembly
which provides the major amount o~ cable movement, moving
the leg supports towards the "splitl' position when the
crank is operated. However, the crank assembly is pivotal-
ly mounted on the base for movement fore and aft. Rollers
are provided in the pivotal mount such that when the crank
housing is moved either foward and/or rearward, the cable
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path is lengthened a slight amount. Thus, tilting the
crank assembly fore and aEt will cause minute and
controlled movements of the leg supports to~ards the
split positionO When not in use, the crank assembly
housing can be tilted flat against the seat portion and
the leg supports can be pivoted to the rear and folded
into and around the body of the apparatus.
More specifically and according to one aspect,
the invention is a leg stretching apparatus for
stretching the legs of a person into a split condition,
said leg stretching apparatus comprising: a lower torso
retaining means for retaining the lower torso of the
person using the apparatus; and means for providing a leg
stretching movement, said movement having a component
directed rearward of said person tending to spread said
person's legs apart, said leg stretching movement
providing means including crank means operative for
providing a major portion of said leg stretching movement
and adjustment means for providing a minor portion of
said leg stretching movement, said adjustment means
comprising a means for adjusting the leg stretching
movement independent of said crank means operation.
According to ano$her aspect, the invention is
a leg stretching apparatus for stretching the legs of a
person into a ~<split position, said apparatus comprising:
a lower torso retaining means for retaining the lower
torso of the person using the apparatus; and means
cantilevered from said lower torso retaining means for
providing a leg stretching movement having a component
directed rearward of said person using said apparatus,
said movement tending to spread said person's legs apart.
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BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention,
and many of the attendant advantages thereof, will be
readily apparent by reference to the accompanying
drawings t wherein:
Figure 1 is a perspective view of an individual
using the present invention;
Figure 2 is a top elevational view showing
the details of the torque disk and cable assembly with
a portion of the upper body being cut away;
Figure 3 is a side view, partially in section,
of Figure 2 taken along section lines 3-3;
Figure 4 is a side view of the upper portion
of the crank assembly housing; and,
Figure 5 is a front end view of the present
invention in the partially folded condition.
DETAILED DESCRIPTION OF PREFERRE~ EMBOVIMENTS
Referring now l.nore particularly to the drawings,
wherein like numerals represent like elements throughout
the several views, Figure 1 generally shows the operator
position and use of the leg stretching apparatus. The
operator 10 is seated on the torso restraining means
comprised of seat assembly 12 and base assembly 14. The
legs are placed in the leg supporting means 16 and 18,
which are spread apart through the action of crank 20
and crank assembly housing 22, as will be seen more
clearly in later figures. Movement of the leg supporting
means is aided through use of a wheel means 24 and 26.
The seat assembly 12 is comprised of two generally
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planar portions 30 and 32 which, in a preferred embodiment,
are connected by a hinge along their contact point (not
shown). In a preferred embodiment, the lower edge of the
planar portions of the:seat are connected to transverse
mounting bars 34 and 36. Each bar in the embodiment shown
has some protruding devic-e, in this instance, a wooden
dowel 38, which fits into corresponding holes in the base
assembly. These dowels prevent movement of the seat
assembly along the surface of the base assembly, and also
permit adjustment of the seat back both in position and
tilt to suit the operator's needs.
In a preferred embodiment, the base assembly is made
up of upper and lower portions, 40 and 42, respectively.
Their spaced-apart relationship is maintained in a preferred
embodiment by spacers 43,-44 and 45, as can be seen in
FIG~RES 1 and 2. In a preferred embodiment, notches 46 are
formed in the lower base portion 42 to accommodate the
wheel means 24 when the leg supporting means are pivoted
back into the storage position.
Each leg supporting means comprises a horizontal,
longitudinally extending portion 50 and a vertical, longitu~
dinally extending portion 52. In a preferred embodiment,
the ~ertical portion is attached to the horizontal portion
by means of hinges 54, which can be more clearly seen in
FIG~RES 2 and 5. By reference to FIGURE 5, it can be seen
that a rather substantial gap is provided between the
vertical portion and the horizontal portion when the leg
supporting means is in the folded position (the right-hand
portion of FIG~E 5) to accommodate the thickness of the
upper base portion 40 and the seat assembly 12 when folded
flat. This ability to fold the leg supporting means
partially into the base assembly and then to fold the
vertical, longitudinally extending portions to a horizontal
position permits the present invention to be stored in a
very small space. It can also be seen that when the ver-
tical portion 52 is in its operating position, it is in
direct contact with the horizontal portion 50, providing a
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relatively rigid connection as far as resisting the pressure
of the.le~s during operation of the apparatus.
By.refer~nce to FIGURE 2, .the or.ientation of the
torque disks 60 to the le~ support:ing means 16, 18 can be
seen. In a preferred emb~diment, th.e torque disk comprises
a disk portion which is fixably secured to the horizontal
portion 50 of the leg supporting means~ The torque disk
and horizontal portion assembly is pivotally mounted by
means of pivots 62, which extends through and between the
upper and lower base portions, 40 and 420 respectively.
Each torque disk has a groove along at least a portion of
the outer periphery of the torque disk so as to accept
cables 63 therein. In a preferred embodiment, a hole 64 is
drilled in the torque disk, the cable 63 inserted there-
through with a fitting swaged or otherwise attached to
the end of the cable to prevent it from being completely
withdrawn through hole 64. Thus, it can be seen when the
ends of cable 63 are pulled towards the.top of FIGURE 2,
both leg supporting means will be rotated towards the rear
of the seat assembly, i.e., forcing the operator's legs
towards the "split".position. For comfort of the operator,
the vertical and horizontal portions of the leg supporting
means may be padded with a vinyl and foam layer 66, as
shown in FIGURE 2. This same material can also be used
effectively to provide a comfortable cover for the seat and
base assembly where the operator's lower torso is in contact
therewith as shown in FIGURE 3.
By reference to FIGURE 3, the operation of the torque
disk 60, which is connected to the horizontal portion 50 of
leg supporting means 16, can be more clearly seen. The
cable runs through a guide means 70 which is attached
through mount 72 to the base assembly. After passing
around guide means 70, both cables travel to the crank
assembly, as shown more clearly in FIGURE 4.
The crank asseJ~ly housing 74 houses a conventional
winch for tig~tening cable 63. A crank handle, upon rotation,
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rotates small gear 77 which, in turn, rotates larger gear
78, which causes drum 80 ~o pull on cable 63 extending from
~uide means 70. A simple spring-biased ratchet 82 control-
lably prevents unwinding of cable 63 from drum 80 when the
crank handle 76 is released. In one embodiment, a friction
brake 84 bears upon a portion of the crank assembly (the
larger gear 78 as shown~ to provide resistance to the with-
drawing of cable 63 from the drum when ratchet 8? is
released. The amount of friction, and thus the amount of
force on cable 63 necessary to unwind it from drum 80, can
be adjusted by means of adjustment 86, to allow the user of
the device not only to stretch his leg muscles but also to
exercise them by forcing the leg supports together in the
non-"split" position. Such adjustable friction brakes are
known in the art and can be adapted to the crank assembly
housing in a conventional manner in view of the previous
discussion. Counter 92 comprises a means for indicating to
the operator the amount of movement of the leg supporting
means.
As previously noted, once the user of the apparatus
has cranked the leg supporting means into a near maximum-
stretch position, it is desirable to be able to increase
the stretch in very small controlled increments. This is
accomplished according to the present invention by pushing
forward and/or pulling back on the crank assembly housing
74. Returning to FIGURE 3, the crank assembly housing 74
is pivotally mounted on mount 72 by pivot 88. This permits
the entire crank assembly housing to be pivoted from its
generally vertical position as shown by letter A forward to
the dotted line position B and rearward to the dotted line
position C. Roller means are provided upon which the
cables may bear when the crank assembly housing is pushed
or pulled into the "B" or "C" positions. In a preferred
embodiment, pivot 88 is a roller means when the housing is
deflected into position "C" and a separate roller means
90 is provided to deflect the cables during movement of
the assembly housing to position "B". It can be seen
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that when the cable is forced to travel around either roller
means, the path that the cable travels from the drum 80 to
the guide means 70 will be increased a very small amount.
Thus, the cable will be pulled from the torque disk towards
the guide means 70, this small amount causing a small and
controlled additional stretching rnovement of the leg support-
ing means.
Thus, the operator, once he has cranked the leg
supporting means into a nearly maximum stretch position, can
tilt the cable assembly housing forward or rearward to add
a slightly additional amount of stretch to his legs.
Because the amount added is very small in r~lation to the
movement of the control housing, there is no danger that a
large amount of leg stretching movement will inadvertently
be added, as is the case with only crank--actuated deviGes.
As has been previously noted, when the apparatus is not
being used, it can be stored in a very compact manner, as
shown in FIGURE 5, by folding the leg supporting means
rearward such that the horizontal portion fits into the
space be~ween the upper and lower base portions and the
vertical portion is folded flat, holding the seat asse~bly
in place in its flat condition. Finally, the crank assembly
housing 74 is folded back to the rear, providing a very
compact and easily stored configuration to the leg
stretching device. Depending on the ultimate user of,such
a device, many different materials could be used for the
upper and lower base portions, the vertical and horizontal
leg supporting portions, and the torque disk and seat
assembly portions. Such materials would include wood~
fib~rboard, plastics, fiberglas, aluminum, and/or metal
materials, as well as others which will become obvious
to those of ordinary skill in view of the previous
discussion. It is also clear that the geometry of the
crank assembly, the ratchet, and the friction brake ~if
desired) could be changed substantially without departing
from the spirit of the present invention. Additionally,
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che ~eometry of the pivoting crank assembly housing could
be changed depending upon how much cable travel. would be
desired.for a given angular displacement of the crank
assembly.housing. Additionally, although the torque disks
were circular and were mounted to pivot: about their center
of curvature, it will be.seen that non-circular perimeters
could be used on the torque disks and/or they could be
mounted away from their centure of curvature~ This would
provide a variation in the amount of leg stretch pex crank
actuation, depending upon how close the user was to the
"split" position. Furthermore, although the use of cables,
torque disks,.and the crank assembly are preferred
embodiments of the present invention, it is well within
the skill of those in the art to substitute a si.mple gear
drive in place thereof, in view of the present disclosure~
Therefore, and in view of the above teachings, many
modifications and applications of the invention will be
obvious to those of ordinary skill in the art. The inven-
tion is not limited to the specific examples ana embodiments
expressed herein, and is limited only in accordance with
~ the appended claims.
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