Exercise board having central mounting with multi-level adjustable spacer

A wobble board is provided with the capability of varying the height between its sphere section and board. The wobble board includes a board with centrally protruding and downward extending bolt. A sphere section having legs, preferably four in number threads to the bolt. In between the sphere section and board underside, a variable height spacer is utilized. Preferably, the variable height spacer is provided with at least two sets of leg receiving notches. These sets of leg receiving notches are each at differing heights relative to the board. At the same time, the position of the notches within each set is complimentary in position to the legs. In operation, height between the sphere section and board is changed by unthreading the sphere section relative to the board without release of the variable height spacer between the sphere section and board. Unthreading continues until leg access to one set of the variable height notches occurs. Thereafter, the legs and spacer are tightened on the threaded attachment until the sphere section at the legs registers to the notches of one set on the spacer. Tightening continues until the sphere section, spacer, and board are locked in a unitary single piece. Exercise with the adjusted spacing between the sphere section and board can then occur.

This invention relates to exercise boards having an exercise platform 
overlying a central pivot. Specifically, the following disclosure sets 
forth an exercise board with a pivot and spacer combination that permits 
adjustable exercise platform height with exercise board disassembly. 
BACKGROUND OF THE INVENTION 
So-called "wobble boards" of the circular variety are known. Specifically, 
a circular board defines an upper exercise surface and has a section of a 
sphere mounted on the under floor exposed side of the board. The person 
undertaking exercise stands or rests on the upward exercise surface. By 
"wobbling" the board to turn on its spherical central support, exercise 
can occur. For example, an injured and recovering basketball player can 
place an injured foot on such a device while shooting so-called "baskets" 
as part of a recovery program. 
It has been found desirable to change the degree of difficulty of such a 
circular wobble board. This is most expeditiously done by changing the 
height between the bottom of the sphere section and the top of the 
circular wobble board. The greater the height between the bottom of the 
sphere and the top of the board, the more difficult exercise becomes. 
Utilizing the example immediately above, the basketball player would 
increase the height between the central pivot and the top of the wobble 
board as his injured ankle improves in recovery. 
Unfortunately, changing the elevation between the sphere section and board 
has proved be other than trivial. Specifically, when it is remembered that 
this is an exercise device, and the full weight--both dynamic and 
static--of athletes are on the board, secure attachment of the sphere 
section with respect to the board is required. To meet this requirement, 
the usual practice has been to use different boards, each with its own 
different sphere section, to adjust board heights. 
SUMMARY OF THE INVENTION 
A wobble board is provided with the capability of varying the height 
between its sphere section and board. The wobble board includes a board 
with centrally protruding and downward extending bolt. A sphere section 
having legs, preferably four in number, threads to the bolt. In between 
the sphere section and board underside, a variable height spacer is 
utilized. Preferably, the variable height spacer is provided with at least 
two sets of leg receiving notches. These sets of leg receiving notches are 
each at differing heights relative to the board. At the same time, the 
position of the notches within each set is complimentary in position to 
the legs. In operation, height between the sphere section and board is 
changed by unthreading the sphere section relative to the board without 
release of the variable height spacer between the sphere section and 
board. Unthreading continues until leg access to one set of the variable 
height notches occurs. Thereafter, the legs and spacer are tightened on 
the threaded attachment until the sphere section at the legs registers to 
the notches of one set on the spacer. Tightening continues until the 
sphere section, spacer, and board are locked in a unitary single piece. 
Exercise with the adjusted spacing between the sphere section and board 
can then occur.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIGS. 1 and 2, the components of the circular wobble board B 
can be seen and identified. The circular wobble board B has circular board 
14 defining board underside 16, and board exercise surface 18. Centrally 
of circular board 14 there protrudes threaded bolt 20, which is here shown 
fastened conventionally by a bolt and washer combination. 
Spacer 22 has board bearing surface 23 for bearing on board underside 16 of 
circular board 14. As viewed in FIG. 1, opposite board bearing surface 23 
spacer 22 defines three notch sets of four (4) notches each. Each notch 
set is at a differing elevation. As will hereinafter become apparent, each 
notch of the set of four notches receives one leg from spherical section 
S. For purposes of simplification, only one notch of each set of four is 
specifically identified; the reader will understand that the remaining 
notches are placed at 90.degree. intervals. 
Lower notch set 24 defines the minimum height spacing between spherical 
section S and board exercise surface 18; this is the "beginner" level for 
circular wobble board B. Medial notch set 26 defines the medium height 
spacing between spherical section S and board exercise surface 18; this is 
the "intermediate" level for circular wobble board B. Highest notch set 28 
defines the highest height spacing between spherical section S and board 
exercise surface 18; this is the "advanced" level for circular wobble 
board B. 
The reader will understand that only two (2) notch sets are required for 
the practice of this invention. We currently prefer three (3) such 
sets--each set being at a different elevation. Additional notch sets could 
as well be used. 
Spherical section S can be easily understood. It includes truncated sphere 
portion 30 for bearing on the typically flat surface against which 
circular wobble board B is placed in use. Additionally, spherical section 
S includes four (4) legs 32 for being received in each of the sets of 
notches 24, 26, and 28. Finally, and in between respective legs 32, 
spherical section S defines sphere truncated intervals 34. These intervals 
permit spherical section S to span the unused notch sets when the device 
is in use. It will be understood that spherical section S contains female 
threads for threading to threaded bolt 20. 
Referring to FIG. 2, assembly and use of circular wobble board B can 
readily be understood. Spherical section S is unscrewed with respect to 
threaded bolt 20. This causes legs 32 of spherical section S to raise 
relative to spacer 22 until one of the respective notch sets 24, 26, or 28 
is received at legs 32 of spherical section S. When this occurs, 
unscrewing stops, and reverse downward and tightening screwing occurs. 
Both spherical section S and spacer 22 frictionally rotate relative to 
circular board 14 at board underside 16 until a friction locked position 
occurs. Upon occurrence of the frictionally locked position, circular 
wobble board B is ready for exercise. 
Two important points need be made. First, each of notch sets 24, 26, and 28 
have lower central portion 40, upper side restraining portion 42, and 
lower side restraining portion 44. When a leg 32 is in a notch, movement 
outside of the notch is inhibited. It has been found that such "notches" 
are to be preferred; otherwise during the dynamics of exercise movement, 
disengagement of legs 32 with the notches can occur. 
Secondly, and especially with respect to FIGS. 3A-3B it can be seen that 
sphere truncated intervals 34 between legs 32 of spherical section S 
effectively span over those notches that are not in use. 
It will be understood that changing between lower notch set 24, medial 
notch set 26, and highest notch set 28, all requires only unscrewing of 
spherical section S relative to threaded bolt 20. Complete detachment of 
spherical section S from circular board 14 never occurs. This has been 
found highly advantageous as experience has proven that spacers requiring 
such disassembly rapidly become lost. 
I have illustrated a threaded connection between the respective parts of 
this invention. It will be understood that other means of fastening will 
work as well. All kinds of mechanical fasteners will operate so long as 
the respective components of the exercise device are held firmly together.