Exercise step with adjustable leg bellows

An exercise step includes a generally rectangular stepping platform having first and second ends and further includes first and second pairs of leg bellows respectively mounted to the first and second ends of the platform thereby forming four legs for supporting the stepping platform above a supporting surface. Each pair of leg bellows is controlled by a single valve for selectively simultaneously inflating or deflating the pair of leg bellows to selectively adjust the height of the platform above a supporting surface. A channel extends between the paired leg bellows at each end of the platform. Each leg bellows includes a flexible air tube extending therefrom, and the air tubes are received in the channels in the bottom of the platform. The valves comprise slotted valve stems which extend into the channels. The paired set of air tubes is received through the slot in the valve stem and the valve stems are slidably movable to open and close paired sets of air tubes in the respective channel to simultaneously control inflation and deflation of each pair of leg bellows.

BACKGROUND AND SUMMARY OF THE INVENTION 
The instant invention relates to exercise step structures and more 
particularly to an exercise step having adjustable support legs. 
Exercise, or aerobic, steps having adjustable leg members have heretofore 
been known in the art. In this regard, the Wilkinson U.S. Pat. No. 
5,127,647; Wilkinson U.S. Pat. No. 5,184,987; and Irwin et al U.S. Pat. 
No. 5,158,512 represent the closest prior art to the subject invention of 
which the applicant is aware. The Wilkinson U.S. Pat. No. 5,127,647 
discloses an adjustable exercise step having a rectangular stepping 
platform and four telescoping legs mounted at the corners of the platform. 
The legs adjustably telescope outwardly for height adjustment. The 
Wilkinson U.S. Pat. No. 5,184,987 and Irwin et al U.S. Pat. No. 5,158,512 
disclose aerobic stepping structures including a platform and a plurality 
of stackable support elements. One or more of the stackable elements are 
utilized to adjust the height of the platform. 
Air filled bladder elements for raising and lowering structures have also 
been known in the art. In this connection, the Douglas U.S. Pat. No. 
2,469,918 and Mason et al U.S. Pat. No. 5,112,045 are also relevant to the 
instant invention. The patent to Douglas discloses an aviation trainer in 
which a plurality of bellows are used to smoothly adjust pitch and roll of 
the trainer. The patent to Mason et al discloses an exercise and 
rehabilitation device comprising a platform and a bladder for supporting 
the platform. The bladder makes the platform unstable when a user stands 
thereon. The object of the exercise is for the user to maintain balance 
while standing on the platform. 
The instant invention provides an exercise step comprising a generally 
rectangular stepping platform having first and second ends, and further 
comprising first and second pairs of leg bellows respectively mounted to 
the first and second ends of the platform thereby forming four legs for 
supporting the stepping platform above a supporting surface. Each pair of 
leg bellows is controlled by a single valve for selectively simultaneously 
inflating or deflating the pair of leg bellows to selectively adjust the 
height and/or angle of the platform above a supporting surface. A channel 
extends between the paired leg bellows at each end of the platform, and 
the valves comprise slotted valve stems which extend into the channels. 
Each leg bellows includes a flexible air tube extending therefrom and the 
air tubes are received in the channels in the bottom of the platform. The 
paired air tubes in the channels are further received through the slots in 
the respective valve stems, wherein the valve stems are slidably movable 
to pinch and unpinch, i.e. close and open, the paired sets of air tubes to 
simultaneously control inflation and deflation of each pair of leg 
bellows. The adjustable leg bellows also enable the platform to be set in 
an inclined position. The air filled leg bellows provide an air suspension 
system which is operable for absorbing impact when a user steps on the 
stepping platform thereby reducing inertial loads on the users leg joints 
during use. 
Accordingly, it is an object of the instant invention to provide an 
exercise step with adjustable leg members. 
It is another object to provide an exercise step having four adjustable leg 
bellows for adjusting the height and angle of the step platform. 
It is yet another object to provide an exercise step having leg bellows 
wherein pairs of leg bellows at opposite ends of the stepping platform are 
operated by a single valve mechanism. 
It is still a further object to provide an exercise step having an air 
suspension support system which absorbs impact and reduces inertial loads 
on the user's leg joints during use. 
Other objects, features and advantages of the invention shall become 
apparent as the description thereof proceeds when considered in connection 
with the accompanying illustrative drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings, the exercise step of the instant invention 
is illustrated and generally indicated at 10 in FIGS. 1-7. As will 
hereinafter be more fully described, the instant exercise step 10 is 
supported on air filled leg bellows which provide an air suspension system 
for relieving stress on the user's legs joints as well as infinite height 
adjustment. 
The instant exercise step 10 comprises a generally rectangular stepping 
platform generally indicated at 12, and four leg bellows generally 
indicated at 14 for supporting the stepping platform 12 above a supporting 
surface. 
The stepping platform 12 is preferably constructed as a singular blow 
molded unit, and it includes upper and lower surfaces generally indicated 
at 16 and 18 respectively, and first and second ends generally indicated 
at 20 and 22 respectively. The upper surface 16 of the stepping platform 
12 includes a central stepping area 24 upon which a user steps during use. 
The stepping area 24 preferably comprises a non-slip material to prevent 
slipping during use. The first and second ends 20 and 22 of the stepping 
platform 12 include integral handle members 26 to facilitate lifting and 
transportation of the exercise step 10. 
The four leg bellows 14 are cylindrical in shape and each comprises a 
pleated expandable body having a bottom end 28 adapted to be received on a 
flat supporting surface, and a top end 30. The top end 30 includes a 
circumferential ridge 32 and an upwardly extending barb shaped air fitting 
34 for inflating and deflating the leg bellows 14. Each leg bellows 14 
further includes a flexible air tube 36 which is slidably received over 
the air fitting 34. The leg bellows 14 are mounted to the bottom surface 
18 of the stepping platform 12 so as to support the stepping platform 12 
above a supporting surface. In this regard, a spaced pair of leg bellows 
14 are mounted adjacent each of the first and second ends 20 and 22 of the 
stepping platform 12 so as to form four spaced supporting legs for the 
stepping platform 12. More specifically, the leg bellows 14 are snap 
received into recesses 38 formed in the bottom surface 18 of the stepping 
platform 12. The recesses 38 each include an annular groove 40 extending 
therearound for snap engagement with the circular ridge 32 of the leg 
bellows 14. 
The bottom surface 18 of the stepping platform 12 further includes a 
transverse channel 42 extending between each spaced paired of recesses 38, 
and a circular depression 44 in the center of each recess 38. When each 
leg bellows 14 is snap received into its respective recesses 38, the barb 
fitting 34 is received into the circular depression 44 in the top of the 
recess 38 and the air tube 36 is received into the adjacent channel 42. 
Referring to FIG. 3-7 the air tubes 36 from each spaced pair of leg 
bellows 14 are received in adjacent relation in their respective channel 
42. 
Each pair of leg bellows 14 is controlled by a independent valve assembly 
generally indicated at 46 for selectively simultaneously inflating or 
deflating the pair of leg bellows 14 to selectively adjust the height of 
the stepping platform 12 above a supporting surface. The valve assemblies 
46 each comprises a slotted valve stem generally indicated at 48 (FIG. 7) 
and a spring 50 (FIG. 7) which are mounted in a circular recess 52 in the 
top surface 16 of the stepping platform 12. The valve stem 48 comprises a 
head portion 54 and a body portion 56 which extends downwardly into the 
adjacent channel 42 through a rectangular guide slot 56 extending 
downwardly from the recess 52. The body portion 56 of the valve 48 stem 
includes a slot 60 therein. In this connection, the paired air tubes 36 in 
the channels 42 are received through the slot 60 in the respective valve 
stems 48 (See FIGS. 3-6). The valve stem 48 is slidably movable in the 
guide slot 58 to pinch and unpinch, i.e. close and open, the air tubes 36. 
More specifically, the valve stem 48 is slidably movable between a first 
upward position (FIGS. 3 and 5) wherein the air tubes 36 are pinched 
closed between the lower end of the valve stem slot 60 and the upper wall 
of the channel 42, and a second downward position (FIGS. 4 and 6) wherein 
the air tubes 36 rest in an unpinched open state while extending through 
the valve stem slot 60. Since the air tubes 36 are paired together in the 
channel 42, the single valve stem 48 is operative for simultaneously 
controlling inflation and deflation of the spaced pair of leg bellows 14. 
The spring 50 is captured between the head portion 54 of the valve stem 48 
and the recess 52 (FIGS. 5 and 6), and it is operative for normally urging 
the valve stem 48 upwardly to normally pinch the air tubes closed (FIG. 
3). 
In use, the air filled leg bellows 14 adjustably expand to provide for 
infinite height adjustment of the stepping platform 12 above a supporting 
surface. To inflate or deflate each pair of leg bellows 14 at the 
respective ends 20 and 22 of the stepping platform 12, i.e. to adjust the 
height of the stepping platform 12, the user depresses the respective 
valve assembly 46 to unpinch the air tubes 36, expands or contracts the 
leg bellows 14 to the height desired, and then releases the valve assembly 
46. The most common use of the exercise step 10 is to have each of the 
four leg bellows 14 positioned at the same height so as to provide a 
horizontal stepping surface, however it is also possible to have one end 
of the step 10 either higher or lower than the other end to provide a 
end-to-end inclined stepping surface. Inclination of the step 10 is 
accomplished by setting one pair of leg bellows 14 at a different height 
then the other pair. While it is readily understood that each valve 
assembly 46 simultaneously controls inflation of each pair of leg bellows 
14, it is also to be understood that the individual leg bellows 14 of each 
pair are nevertheless individually expandable. In this connection, the one 
leg bellows 14 of a pair is positioned higher or lower than the other leg 
bellows 14, to give the exercise step 10 the ability to be positioned in a 
front-to-back inclined position. 
The leg bellows 14 further provide an air cushioned suspension system for 
the stepping platform 12. The air suspension leg bellows 14 absorb the 
downward impact of a user's weight as the user steps thereon and thereby 
reduce inertial loads on the users leg joints during use. The air 
suspension bellows 14 therefore make aerobic stepping exercises more 
comfortable and safer to perform. 
Referring to FIGS. 8 and 9, second and third alternative embodiments of the 
instant exercise step are illustrated and respectively indicated at 10A 
and 10B. The second embodiment 10A comprises a stepping platform 12 as 
previously described, however there are two generally rectangular shaped 
leg bellows 14A mounted to the bottom of the platform 12 instead of four 
cylindrical leg bellows 14 as previously described. The two rectangular 
leg bellows 14A are individually controlled for inflation and deflation. 
The third embodiment 10B also includes a stepping platform 12 as 
previously described, however the stepping platform 12 is supported by a 
single rectangular bellows 14B which covers substantially entirely the 
bottom surface of the platform 12. While these alternative embodiments 10A 
and 10B have virtually the same operational characteristics as the 
preferred device 10, the larger rectangular bellows 14 A and 14B are more 
difficult and more expensive to manufacture than the smaller cylindrical 
leg bellows 14, thereby making the second and third embodiments 10A and 
10B more expensive to market. 
It can therefore be seen that the instant invention provides a unique 
exercise step 10. The exercise step 10 is supported on one or more 
expandable leg bellows 14 which provide for infinite height and angle 
adjustment. The leg bellows 14 further provide an air suspension system 
which absorbs impact energy of a user stepping thereon thereby reducing 
inertial loads on the users leg joints. Inflation and deflation of the leg 
bellows 14 is controlled by a simple valve mechanism 46 which is depresses 
to inflate or deflate and released to maintain in a steady state 
condition. When four leg bellows 14 are mounted in the corners of the 
platform, the paired leg bellows 14 at each end of the platform 12 are 
controlled by a single valve assembly 46 to simultaneously and selectively 
control inflation and deflation of the paired leg bellows 14. For these 
reasons, the instant invention is believed to represent a significant 
advancement in the art which has substantial commercial merit. 
While there is shown and described herein certain specific structure 
embodying the invention, it will be manifest to those skilled in the art 
that various modifications and rearrangements of the parts may be made 
without departing from the spirit and scope of the underlying inventive 
concept and that the same is not limited to the particular forms herein 
shown and described except insofar as indicated by the scope of the 
appended claims.