Slip-on attachment for skateboards

A slip-on attachment apparatus (10) for the conventional wheels (100) of a typical skateboard device (101) wherein the attachment apparatus (10) comprises a plurality of attachment members (11) including a generally elongated hollow cylindrical housing (13) having at least one outwardly and radially disposed narrow runner element (12) formed thereon; wherein, the interior of the cylindrical housing (13) is adapted to engage the outer periphery of the wheels (100) of a skateboard (101).

TECHNICAL FIELD 
The present invention relates in general to convertible arrangements for 
skateboards; and, in particular to a slip-on adapter to convert the wheel 
configuration on a skateboard. 
BACKGROUND OF THE INVENTION 
As can be seen by reference to the following U.S. Pat. Nos. 4,043,565; 
4,114,913; 3,626,774; and, 4,116,455 the prior art is replete with myriad 
and diverse substitute wheel constructions that are intended to convert 
the typical rolling wheel transport of the skateboard into a sliding 
runner mode of transport. 
Unfortunately as is the case with the aforementioned prior art devices, the 
uniform method of affecting the conversion of the skateboard from wheels 
to runners requires the physical substitution of a runner element after 
the wheel element has been physically removed from the skateboard axle. 
While this substitution process admittedly produces a converted skateboard 
apparatus that is more than adequate for the purpose and function for 
which the skateboard was converted; this process involves multiple steps, 
significant physical exertion, the expenditure of a great deal of time; 
and, the use of specialized tools to remove the wheel and install the 
runner. 
In view of the foregoing situation there has obviously existed a long 
standing need among users of skateboards for a quickly and simply 
installed conversion arrangement that could be attached and detached from 
the skateboard in a matter of seconds without the use of tools; and, which 
would also not require that the standard equipment wheels be removed from 
the skateboard axles. 
BRIEF SUMMARY OF THE INVENTION 
The present invention involves in general a slip-on attachment unit that 
will engage the periphery of the conventional wheels of a skateboard to 
convert the configuration of the surface contacting portion of the 
conventional wheels into a quasi-runner configuration; whereby, the 
converted skateboard construction will be adapted for use on relatively 
slick surfaces such as ice and snow. 
The slip-on attachment unit comprises in general a generally hollow 
cylindrical attachment member which is adapted to fit over and 
frictionally engage the ground contacting periphery of the conventional 
skateboard wheels; wherein, the attachment member is provided with at 
least one radially disposed relatively narrow runner element that projects 
outwardly from the periphery of the attachment member. 
In addition, by virtue of the frictional engagement between the attachment 
member and the conventional skateboard wheel, the wheel will not be 
restrained from rotation about its related axle; however, the attachment 
member will now only make narrow rotary point contact with the surface 
being traversed by the skateboard, by virtue of the presence of the at 
least one runner element on the attachment member. 
Furthermore, the design and construction of the slip-on attachment unit 
will allow a skateboard to be converted in a matter of seconds without the 
use of any tools nor any particular degree of manual dexterity. 
Conversely, the skateboard may be returned to its normal wheeled 
configuration in a like manner and without a great deal of physical 
exertion.

BEST MODE FOR CARRYING OUT THE INVENTION 
As can be seen by reference to the drawings and in particular to FIG. 1, 
the slip-on skate attachment apparatus that forms the basis of the present 
invention is designated generally by the reference numeral (10) and is 
intended for use in conjunction with the conventional wheels (100) of a 
typical skateboard device (101). The attachment apparatus (10) comprises 
in general a plurality of attachment members (11); wherein each attachment 
member is provided with at least one narrow outwardly and radially 
disposed runner element (12). 
As can best be appreciated by reference to FIGS. 1 and 2, each of the 
attachment members (11) comprise a generally elongated hollow cylindrical 
housing (13) having an open inboard end (14) and a closed outboard end 
(14'); wherein, the interior walls (15) of the hollow cylindrical housing 
(13) are dimensioned and designed to receive and frictionally engage the 
periphery (100') of one of the conventional wheels (100) of a skateboard. 
Furthermore, the closed outboard end (14') of the housing will serve to 
limit the amount of lateral travel that may be permitted between the wheel 
(100) and the cylindrical housing (13). 
As can also be seen by reference to FIGS. 1 and 2, the cylindrical housing 
(13) of the preferred embodiment is actually provided with a plurality of 
relatively narrow runner elements (12) that are spaced from one another 
and radially disposed on the periphery of the cylindrical housing (13); 
wherein the outboard ends of the radial runner elements (12) terminate in 
pointed runner blade members (16). 
As shown in FIGS. 2 thru 8, some of the runner blade members (16) 
contemplated for use in this invention have a single blade configuration 
(16') (i.e. FIGS. 2, 5, and 8) while other runner blade members (16) have 
a double blade configuration (16") (i.e. FIGS. 3, 4, 6 and 7). In the 
single blade embodiment (16') illustrated in FIG. 2, the runner blade 
members (16) are provided with a generally sharp knife blade edge 
cross-section. In the single blade embodiments (16') illustrated in FIG. 
5, the runner blade members (16) are provided with a generally blunt knife 
blade edge cross-section; and, in FIG. 8 the runner blade members (16) are 
provided with a stepped shoulder pin joint edge cross-sectional 
configuration. 
With respect to the double blade embodiments, as shown in FIG. 3, the 
outboard blade (19) terminates in a vertical face (20); wherein an arcuate 
recess (21) is formed between the inboard (22) and outboard (19) blades; 
and, wherein the inboard edge of the inboard blade (22) terminates in a 
tapered wall (23). 
In the version depicted in FIG. 4, the outboard blade (19) also terminates 
in a vertical face (20); wherein a V-shaped notch (24) is formed between 
the inboard (22) and outboard (19) blades; and, wherein the inboard blade 
(22) terminates in a vertical face (25). 
In the version depicted in FIG. 6, both the inboard (22) and outboard 
blades are provided with tapered faces (26); wherein, the intermediate 
tapered faces form a V-shaped notch (24); and, in the version depicted in 
FIG. 7 both the inboard (22) and outboard (19) terminal edges form tapered 
faces (27); and, an arcuate recess (21) is formed intermediate the 
outboard (19) and inboard (22) blades. 
At this juncture it should be appreciated that the skate attachment 
apparatus (10) of this invention allows a conventional wheeled skateboard 
(101) to be instantaneously converted into a multi-bladed runner 
undercarriage simply by the provision of slipping the cylindrical 
attachment members (11) over the wheels (100) of the skateboard (101); 
thereby allowing the converted skateboard to be functionally deployed on 
slippery surfaces such as snow or ice. In addition, the plurality of 
runner elements (12) on each of the attachment members (11) enhances the 
frictional engagement and maneuvering control of the converted skateboard 
relative to the aforementioned slippery surfaces. 
Having thereby described the subject matter of this invention, it should be 
obvious that many substitutions, modifications, and variations of the 
invention are possible in light of the above teachings. It is therefore to 
be understood that the invention as taught and described herein is only to 
be limited to the extent of the breadth and scope of the appended claims.