Leg stretching apparatus

Disclosed are two separate leg supporting members which are independently pivotally connected to a base assembly. At their pivotal connection with the base assembly they are further provided with a disk assembly having a cable attached thereto. The cable from each leg supporting member is attached through guide means to a crank assembly which, during operation, forces the leg supporting members apart stretching the legs of a user of a device into a "split" position. The crank assembly housing is pivotally mounted such that when the housing is moved forward and/or rearward, the cable path of both cables is lengthened a small amount, providing the user with a controlled minute additional stretching movement. The leg supporting members during non-use are retractable partially into the base assembly and a torso retaining seat back assembly can be folded flat. The crank housing assembly can also be folded down on top of the seat back assembly providing a very compact storage configuration. In a preferred embodiment, a friction brake device is affixed to the crank assembly such that the user can straighten his legs away from the "split" position, thus strengthening his leg muscles as well as stretching them.

BACKGROUND OF THE INVENTION 
The present invention relates generally to athletic equipment and relates 
specifically to a leg stretching apparatus. 
Dancers, 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" position, 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 respect 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 progressively 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 progressively 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 possible damage thereto. 
Another device currently on the market permits the operator to sit on the 
device with each leg being independently supported. The leg supporting 
devices are pivotally attached to the central portion of the machine upon 
which the individual is seated. Cables extend from the outer portion 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 
cables 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 adjustments 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. 
SUMMARY OF THE INVENTION 
Therefore, in view of the above and other disadvantages 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 
within 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 leg supports and to provide a further apparatus for 
applying minute and contolled stretching movements to the leg supports 
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 folded 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 applying minute and controlled 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 through a guide and go up to a 
conventional crank and drum assembly which provides the major amount of 
cable movement, moving the leg supports towards the "split" position when 
the crank is operated. However, the crank assembly is pivotally 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 path is lengthened a slight amount. Thus, tilting the 
crank assemby fore and aft will cause minute and controlled movements of 
the leg supports towards the "split" position. 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.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
Referring now more particularly to the drawings, wherein like numerals 
represent like elements throughout the several views, FIG. 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 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 device, 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 FIGS. 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, longitudinally extending portion 52. In a 
preferred embodiment, the vertical portion is attached to the horizontal 
portion by means of hinges 54, which can be more clearly seen in FIGS. 2 
and 5. By reference to FIG. 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. 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 vertical portion 52 is in its operating 
position, it is in direct contact with the horizontal portion 50, 
providing a relatively rigid connection as far as resisting the pressure 
of the legs during operation of the apparatus. 
By reference to FIG. 2, the orientation of the torque disks 60 to the leg 
supporting means 16, 18 can be seen. In a preferred embodiment, the 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 42, 
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 therethrough 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 FIG. 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 FIG. 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 FIG. 3. 
By reference to FIG. 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 FIG. 4. 
The crank assembly housing 74 houses a conventional winch for tightening 
cable 63. A crank handle, upon rotation, rotates small gear 77 which, in 
turn, rotates larger gear 78, which causes drum 80 to pull on cable 63 
extending from guide means 70. A simple spring-biased ratchet 82 
controllably 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 withdrawing of cable 63 from the drum when ratchet 82 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 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 FIG. 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 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 movement of the leg supporting 
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 relation 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 devices. 
As has been previously noted, when the apparatus is not being used, it can 
be stored in a very compact manner, as shown in FIG. 5, by folding the leg 
supporting means rearward such that the horizontal portion fits into the 
space between the upper and lower base portions and the vertical portion 
is folded flat, holding the seat assembly 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, fiberboard, 
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, the geometry 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 per 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 simple 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 invention is not limited to the specific 
examples and embodiments expressed herein, and is limited only in 
accordance with the appended claims.