Roller skate apparatus

An improved roller skate apparatus is disclosed and preferably includes a bifurcated truck assembly that is interlockingly and removably attached to a sole plate, as well as a quick-change wheel and axle apparatus. At least in a two-wheeled version of the roller skate apparatus, the wheels preferably include a generally flat horizontal central portion on the ground-engaging wheel periphery in order to provide greater ease and stability in two-wheeled skating. Various adjustable and quick-change toe stop embodiments are also enclosed.

BACKGROUND AND SUMMARY OF THE INVENTION 
The invention relates generally to roller skates, or roller skate-type 
devices, and more particularly to support structure assemblies and axle 
and wheel assemblies therefor. 
In light of the recent emphasis on, and greatly increased participation in, 
physical activities and competitive sports, both recreational and 
competitive roller skating has emerged as a more significant and 
sophisticated pastime than it was in the past. As a result, the emphasis 
upon the production of sophisticated and high quality roller skating 
equipment has rapidly increased. Furthermore, both two and four-wheeled 
roller skating has been used to train and condition participants even in 
non-roller skating athletic programs. 
Because of the increased significance and sophistication of roller skating, 
in both competition and training activities, the materials and designs for 
wheels and other skate equipment have become quite specialized for various 
applications and purposes. As a result, some wheels and other equipment 
have specialized configurations or compositions that are not well-suited 
for a wide variety of skating applications. Furthermore, especially in the 
area of two-wheeled roller skating, such specialization and sophistication 
of wheels and other skate equipment has been found to require a relatively 
high amount of instruction and training in order to allow participants, 
especially beginners, to use them. Accordingly, the need has arisen for 
roller skate equipment that has a high degree of adaptability for various 
specialized activities, while still maintaining a high degree of 
sophistication and suitability for such divergent activities. Furthermore, 
the need has arisen, especially in two-wheeled roller skating, for 
equipment that allows earlier participation by the beginner, without 
sacrificing the unique effects and benefits of two-wheeled skating. 
According to at least one preferred embodiment of the present invention, a 
roller skate wheel member has a generally toroidal configuration with a 
ground-engaging peripheral surface extending circumferentially 
therearound. In this embodiment of the invention, which is particularly 
adapted for two-wheeled roller skates, the ground-engaging peripheral 
surface of each wheel member includes an axially central portion that is 
generally flat in its diametric cross-sectional configuration and that 
preferably extends axially in a direction generally parallel to the wheel 
member's axis of rotation. Preferably, the ground-engaging peripheral 
surface of each wheel member further includes an arcuate portion disposed 
axially adjacent one or both sides of the central portion and which curves 
generally radially inwardly therefrom. 
Another preferred embodiment of the present invention includes a 
quick-change wheel mounting and removal apparatus, which can be used on 
roller skates having any number of wheels and which can be employed 
separately or in conjunction with the above-discussed wheel configuration. 
In one form of this embodiment, a truck assembly for supporting a sole 
plate includes at least two separate truck members with attachment means 
for removably attaching teh truck members to one another in a mutual 
mating relationship. At least one axle member, which is adapted to 
removably receive one or more wheels for rotation thereon, includes a 
portion thereof that is attached to one of the truck members, with the 
other of the truck members having means thereon for receiving and 
removably engaging the axle when the truck members are attached to one 
another. The wheel or wheels can therefore be mounted on, or removed from, 
the axle or axles when the truck members are detached from one another and 
are restrained but freely rotatable when the truck members are attached. 
In another preferred embodiment of the present invention, the truck 
assembly of the roller skate is attachable to a sole plate by interlocking 
means, preferably without the necessity of threaded or other types of 
fasteners extending between and interconnecting the truck assembly and the 
sole plate. 
In still other embodiments of the invention, the wheels and other skating 
accessories or devices are adapted to be quickly and conveniently mounted 
and detached in order to prepare the skate for a wide variety of skating 
applications and events. 
Additional objects, advantages, features and embodiments of the present 
invention will become apparent from the following description and appended 
claims, taken in conjunction with the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIGS. 1 through 20 depict various preferred exemplary embodiments of an 
improved roller skate apparatus according to the present invention. One 
skilled in the art will readily recognize from the following discussion 
that the various embodiments of the invention are equally applicable to 
roller skate apparatus having virtually any number of wheels, axles, and 
combinations thereof, as well as being applicable to other skate-like 
devices. 
FIGS. 1 through 4 illustrate a roller skate 10, generally including a boot, 
shoe, or other similar footwear item 12, supported and suspended upon a 
support structure assembly 16. The support structure assembly 16 generally 
includes a sole plate 18 with a truck assembly 20 removably attachable to 
a lower surface 22 of the sole plate 18 in the exemplary roller skate 10. 
A pair of wheels 24 include bearing members or assemblies 28 thereon and 
are removably mounted on the support structure assembly 16 for rotation 
about their respective axles 26. It should be understood, however, that 
the exemplary roller skate 10 can include more than two wheels 24 and can 
have more than one wheel 24 rotatably mounted upon one or more of the 
axles 26. 
The wheels 24 can be composed of various durable materials known to those 
skilled in the art, such as polyurethane, polycarbonate, or light-weight 
metals, and are formed in a generally toroidal configuration, with a 
ground-engaging peripheral surface 32 extending around their 
circumference. At least in the illustrated exemplary two-wheeled version 
of the roller skate 10, the ground-engaging peripheral surface 32 
preferably includes a central portion 34 that is generally flat in its 
diametric cross-section and that extends axially in a direction generally 
parallel to the axles 26 of the wheel 24, as shown in FIG. 4. The 
ground-engaging peripheral surface 32 also includes at least one, and 
preferably two, arcuate portions 36 disposed axially adjacent the central 
portion 34 and curving generally radially inwardly therefrom. Preferably, 
the flat central portion 34 has an axial width of at least 50% of the 
total axial width of the wheel 24. 
As shown in FIGS. 2, 3, and 5 through 9, one preferred embodiment of the 
truck assembly 20 includes at least a pair of truck members 40a and 40b 
adapted to be removably attached to one another in a generally mutual 
mating relationship along their respective mutual mating surfaces 42a and 
42b. The preferred truck members 40a and 40b each include a number of 
corresponding forward axle support portions 44a and 44b, and a number of 
corresponding rearward axle support portions 45a and 45b, respectively. At 
least one of the forward axle support portion combinations 44a and 44b is 
preferably located so as to be centered under the ball of the 
skate-wearer's foot, and at least one of the rearward axle support portion 
combinations 45a and 45b is preferably centered under the wearer's heel. 
The exact number of such axle support portions in a given application, 
however, corresponds to the number of axles 26. 
At least one (and preferably both) of the axle support portions 44a or 44b 
and 45a or 45b on the respective truck members 40a or 40b, respectively, 
preferably has an end portion of its respective axle 26 press-fit into an 
aperture 46 or otherwise substantially fixed thereto. The corresponding 
axle support portion (or portions) on the other of the truck members 40a 
or 40b includes a corresponding axle-receiving aperture 48, or other 
suitable means for removably engaging and supporting the axle, therein. 
The preferred axle receiving apertures 48 are adapted to slidably receive 
the opposite ends of the respective axles 26 in a supporting slip-fit 
relationship therewith such that the wheels 24 may be slidably mounted on, 
or removed from, their axles 26 when the truck members 40a and 40b are 
separated. Accordingly, when the wheels 24 are mounted on their axles 26, 
and the truck members 40a and 40b are removably attached to one another, 
the wheels 24 are restrained on the truck assembly 20 but are freely 
rotatable about their respective axles 26. It should be noted that the 
truck members 40a and 40b can be removably attached to one another by way 
of a a number of threaded fasteners 50, for example, extending through 
apertures 52a and 52b in the truck members 40a and 40b, respectively. One 
skilled in the art will readily recognize, however, that other suitable 
attachment means may alternatively be employed for removably attaching the 
truck members 40a and 40b to one another. 
Referring primarily to FIGS. 2, 3, and 5 through 12, the lower surface 22 
of the sole plate 18 preferably includes a forward interlock member 56, an 
intermediate interlock member 58, and a rearward interlock member 60, all 
in the form of downwardly-protruding surface discontinuities thereon. 
Correspondingly, the truck assembly 20 includes openings therein, which 
form a forward interlock receptacle 62, an intermediate interlock 
receptacle 64 and a rearward interlock receptacle 66 between the truck 
members 40a and 40b. As will be described in detail below, the interlock 
receptacles 62, 64 and 66 are adapted for interlockingly and removably 
receiving and engaging the corresponding interlock members 56, 58 and 60, 
respectively, in order to removably and interlockingly attach the sole 
plate 18 and the truck assembly 20 to one another. It should be noted that 
although three sets of interlock member and interlock receptacle 
combinations are shown for purposes of illustration in the drawings, the 
sole plate 18 and the truck assembly 20 may include one or more of such 
combinations. 
The interlock members 56, 58 and 60 include undercut edge portions 68, 70 
and 72 preferably extending around at least a substantial portion of their 
respective peripheries. Preferably, at least the forward interlock member 
56 and the rearward interlock member 60 are generally plate-shaped in 
configuration, with their respective undercut edge portions 68 and 72 
beveled generally upwardly and inwardly toward the bottom surface 22 of 
the sole plate 18 such that the lower surface area of the interlock 
members 56 and 60 is greater than their corresponding horizontal 
cross-sectional areas. 
The forward interlock receptacle 62, the intermediate interlock receptacle 
64, and the rearward interlock receptacle 66 are defined at least in part 
by respective peripheral walls 74, 76 and 78. The peripheral walls 74, 76 
and 78 include undercut peripheral wall portions 80, 82 and 84, 
respectively, on at least part of their peripheries. The undercut 
peripheral wall portions 80, 82 and 84 of the respective interlock 
receptacles 62, 64 and 66 are adapted to interlockingly and removably 
engage the corresponding undercut edge portions 68, 70 and 72 of the 
corresponding interlock members 56, 58 and 60, respectively. 
Preferably, at least the intermediate interlock member 58 is defined by an 
elongated generally rod-shaped member 86 extending generally 
longitudinally along the lower surface 22 of the sole plate 18 and 
interconnected therewith by an elongated interconnecting member 88. The 
lateral width of the interconnecting member 88 is less than that of the 
rod-shaped member 86 in order to form the above-mentioned undercut edge 
configuration 70. Correspondingly, the undercut wall portion 82 of the 
intermediate interlock receptacle 64 has a configuration that is 
receivingly complementary to that of the undercut edge portion 68 formed 
and defined by the rod-shaped member 86 and the interconnecting member 88, 
thereby providing for the above-discussed removable and interlocking 
engagement. 
In the preferred embodiment of the support structure assembly 16, the 
mutual mating surfaces 42a and 42b of the truck members 40a and 40b, 
respectively, extend longitudinally generally along the longitudinal 
centerline 90 of the truck assembly 20. Preferably, the centerline 90 is 
generally colinear with the longitudinal centerline 92 of the sole plate 
18 when the truck members 40a and 40b are attached to one another with the 
truck assembly 20 removably attached to the sole plate 18. The interlock 
members 58, 60 and 62 are preferably located on the sole plate 18 such 
that they are each bisected into two generally equal parts by the 
longitudinal centerline 92, and the corresponding interlock receptacle 62, 
64 and 66 are preferably symmetrically formed along or adjacent to the 
respective mutual mating surfaces 42a and 42b of the truck members 40a and 
40b. Therefore, when the truck members 40a and 40b are moved into their 
mutual mating engagement, while in contact with the lower surface 22 of 
the sole plate 18, the interlock receptacle 62, 64 and 66 interlockingly 
receive and engage the interlock members 56, 58 and 60, respectively, as 
described above. 
The attachment of the truck members 40a and 40b to one another, can be by 
way of the exemplary threaded fasteners 50 extending through the apertures 
52, for example, and therefore serves to secure the truck assembly 20 to 
the sole plate 18 because of the above-mentioned interlocking engagement 
of the interlock members and their corresponding interlock receptacles. 
Preferably, either the interlock members 56, 58 and 60, or at least the 
portions of the truck members 40a and 40b adjacent the interlock 
receptacles 62, 64 and 66, are composed of a resilient and compliant 
material in order to assure a relatively tight interlocking engagement 
between the interlock members and their corresponding interlock 
receptacles. 
As shown in FIG. 10, the sole plate 18 can integrally comprise the sole 
portion of the boot, shoe or other footwear item 12 of the roller skate 
10. Alternatively, as shown in FIG. 11, an alternate sole plate 18a can be 
either fixedly or removably secured to the sole portion 14 of a sport shoe 
13 or some other similar footwear item. One skilled in the art will 
readily recognize that the sole plate 18a in FIG. 11 may be attached or 
secured to the sole portion 14 by an adhesive material, by releasable 
clamp or clip members, or by other suitable attachment means known in the 
art. Although the support structure assemblies 16 and 16a are shown for 
purposes of illustration in FIGS. 10 and 11, one skilled in the art will 
also recognize that the other support structure assemblies shown in the 
drawings and discussed below can also alternatively be an integral part of 
a footwear item or can be fixedly or removably secured thereto. 
Referring primarily to FIGS. 12 through 14, at least one of the sets of the 
forward axle support portions 44a and 44b, or the rearward axle support 
portions 45a and 45b, can optionally include insert sleeves 94 in their 
respective axle receiving apertures 48 for receiving and engaging their 
respective axles 26. Whether or not such insert sleeves 94 are employed, 
the bearing assemblies 28 can optionally include a resilient bearing 
sleeve 96 disposed between the bearing assembly 28 (or an inner bearing 
sleeve portion 30 thereof) and the axle 26. The resilient bearing sleeve 
96 resiliently suspends the support structure assembly 16 relative to the 
wheel members 24 and resiliently allows for movement or shifting of the 
axis of rotation of the wheel members 24 relative to the axles 26. Such 
relative movement or shifting can occur during any of a number of roller 
skating maneuvers, such as cornering, for example. 
FIG. 14 illustrates an alternate configuration for providing resiliency 
between the wheels 24 and the support structure assembly 16. As shown in 
FIG. 14, at least one bearing member 28 of a wheel 24 directly engages the 
corresponding axle 26, and resilient insert sleeves 98 are disposed 
between the axle 26 and the support structure assembly 16 (or the insert 
sleeves 94 thereof). Both the resilient bearing sleeves 96 and the 
resilient insert sleeves 98 shown alternatively in FIGS. 13 and 14 are 
preferably comprised of an elastomeric material and have a generally 
cylindrical configuration with an open-ended aperture extending axially 
therethrough. 
FIGS. 15 through 18 illustrate alternate embodiments of the quick-change 
wheel and axle features of the present invention for use in a support 
structure assembly 116 having a truck assembly 120 that is not necessarily 
split into separate truck members. It should be noted that the alternate 
embodiments shown in FIGS. 15 through 18 are applicable to roller skates 
having wheels 124 that are sufficiently narrow to fit between the axle 
receiving portions 144 on the truck assembly 120. It should be noted that 
any of the quick-change axle mechanisms or assemblies shown in FIGS. 15 
through 18 can also optionally be employed in conjunction with the support 
structure assembly 16 and the split truck assembly 20 shown above, as well 
as the various variations thereon. 
In FIG. 15, at least one (and preferably both) of the axle receiving 
portions 144 on the truck assembly 120 includes an aperture 148 extending 
therethrough and having an open end 150 thereon. The aperture (or 
apertures) 148 in the truck assembly 120 are positioned so as to align 
with the axle receiving openings in the bearing assemblies 128 on the 
wheels 124. The apertures 148 are adapted to receive an axle 126 inserted 
through their open ends 150, with the axle 126 being adapted and sized for 
a substantially press-fit frictional relationship within the apertures 
148. Accordingly, in order to quickly and conveniently remove or install 
the wheels 124 on the truck assembly 120, the axles 126 are forcibly 
driven out of, or into, their frictional press-fit engagement with the 
apertures 148 in the axle receiving portions 144. 
FIG. 16 illustrates another alternate quick-change axle and wheel assembly 
having a collapsible axle assembly 154 engageable with apertures 156 and 
158 in the axle receiving portions 144a of the truck assembly 120a. The 
collapsible axle assembly 154 shown in FIG. 16 preferably includes a 
generally hollow sleeve member 160 having a closed end 162 and an open end 
164 thereon. The sleeve member 160 is adapted to slidably receive at least 
a portion of a generally cylindrical axle rod member 166 therein with a 
resilient member, such as the spring member 168, disposed within the 
sleeve member 160 between the closed end 162 and the axle rod member 166. 
When the collapsible axle assembly 154 is mounted between the spaced-apart 
axle receiving portions 144a, the spring member 168 resiliently biases the 
axle rod member 166 and the closed end 162 of the sleeve member 160 away 
from one another and into engagement with the axle receiving portions 
144a. 
In order to conveniently and quickly remove the wheel 124 from the truck 
assembly 120a, apertures 170 are provided in the axle receiving portions 
144a. The apertures 170 are adapted to receive a rod or tool member 
insertable therein for forcibly sliding the axle rod member 166 and the 
closed end 162 of the sleeve member 160 toward one another against the 
biasing force of the spring member 168 in order to collapse and shorten 
the axle assembly 154. When the axle assembly 154 is sufficiently 
shortened, the wheel 124 and the collapsed axle assembly 154 may be 
removed from between the axle receiving portions 144a. The wheel 124 may 
then be slidably removed from the axle assembly 154 in order to effect the 
desired wheel change. In order to reinstall the wheel 124 and the axle 
assembly 154, the axle assembly 154 is collapsed and shortened 
sufficiently to allow it to fit between the axle receiving portions 144a 
and then released to be received within the apertures 148. It should be 
noted that either or both of the apertures 148 in the axle receiving 
portions 144a may also include an insert sleeve 130a with an opening 132 
in its end for receiving the tool member 172 therethrough. 
FIG. 17 illustrates another alternate quick-change axle apparatus having an 
axle member 174 with a threaded end portion 176 and a tool-engaging 
portion 178 thereon. In order to remove or install the axle member 174 
between the axle receiving portions 144b, a tool member 177 is inserted 
through an open end 179 of an aperture 180 in one of the axle receiving 
portions 144b. The tool member 177 is used to selectively rotate the axle 
member 174 into or out of threadable engagement with a threaded insert 
sleeve 130b in the opposite axle receiving portion 144b. Once the axle 
member 174 is rotated and threadably released so as to be removed from the 
truck assembly 120b, the wheel 124 is free to be removed from between the 
axle receiving portions 144b. When the wheel 124 is to be installed on the 
truck assembly 120b, the above procedure is reversed, and the tool member 
172 is used to rotate the axle member 174 into threadable engagement with 
the insert sleeve member 130b, thereby securing the axle member 174 and 
the wheel 124 to the truck assembly 120b. 
FIG. 18 illustrates still another alternate embodiment of a quick-change 
wheel and axle arrangement according to the present invention. A 
collapsible axle assembly 184 shown in FIG. 18 includes a generally 
cylindrical axle rod member 185 having a shank portion 186 and a threaded 
portion 188 thereon. The threaded portion 188 is adapted to threadably 
engage an internally-threaded cylindrical sleeve member 190 such that the 
axle rod member 185 and the sleeve member 190 may be selectively rotated 
relative to one another and threadably urge the rod member 185 toward or 
away from the closed end 191 of the sleeve member 190, thereby selectively 
increasing or decreasing the overall length of the collapsible axle 
assembly 184. Such relative rotation is accomplished by inserting a tool 
member 177 through an aperture 180c in one of the axle receiving portions 
144c and engaging a tool-engaging portion 192 of the axle rod member 185. 
Simultaneously, another tool member 182 is inserted through an aperture 
170c in the other of the axle receiving portions 144 and is placed in 
engagement with a tool engaging portion 194 on the closed end 191 of the 
sleeve member 190. 
Similar to the resilient collapsible axle assembly 154 shown in FIG. 16, 
the overall length of the collapsible axle assembly 184 in FIG. 18 may be 
shortened sufficiently to allow the axle assembly 184 and the wheel 124 to 
be removed from between the axle receiving portions 144c. In order to 
reinstall the wheel 124 and the axle assembly 184, the above procedure is 
reversed. The axle rod member 185 and the sleeve member 190 are rotated in 
a direction to threadably urge the rod member 185 away from the closed end 
191 of the sleeve member 190, thereby lengthening the axle assembly 184 
and urging into engagement with the axle receiving portions 144. 
It should be noted that any of the above-discussed embodiments of the 
roller skate apparatus according to the present invention can also 
optionally include a toe stop device on its forward end. Such toe stop 
devices are frequently desirable for allowing the wearer of the roller 
skate to merely tip the skate forward such that the toe stop member 
frictionally engages the ground or floor upon which the wearer is skating 
and acts as a brake for slowing or halting his or her progress. 
In FIG. 2, one embodiment of a top stop apparatus 102 includes a frictional 
element 104 and a threaded rod member 106 adapted to threadably engage a 
threaded aperture 108 in the truck assembly 20. By rotating the toe stop 
apparatus 102 the position of the friction element 104 relative to the 
truck assembly 20 may be adjusted to provide the desired clearance between 
the friction element 104 and the ground or floor upon which the user is 
skating. Once the desired relative position between the friction element 
104 and the truck assembly 20 is achieved, a jam nut 110 may be threadably 
tightened into engagement with the truck assembly 20, thereby 
substantially preventing the toe stop apparatus 102 from undesired 
rotation. 
FIG. 19 illustrates an alternate toe stop apparatus 202 including a 
friction element 204 with an integral interlock member 206 thereon. In the 
embodiment illustrated in FIG. 19, the truck assembly 220 includes an 
interlock receptacle 208 located on a forward portion thereof and adapted 
for interlockingly and removably receiving the interlock member 206 
therein. Like the interlock members 56 and 58 and the interlock 
receptacles 62 and 66 described above, the interlock member 206 includes a 
beveled undercut edge portion 210 which is interlockingly and removably 
engageable with an undercut peripheral wall portion 214 of a peripheral 
wall 212 that at least in part defines the interlock receptacle 208. The 
interlock receptacle 208 is preferably located on the truck assembly 220 
so that it is bisected into two generally equal parts when the truck 
members 240a and 240b are separated along their respective mutually mating 
surfaces 242a and 242b. Thus, when the truck members 240a and 240b are 
attached to one another with the interlock member 206 interlockingly 
received by the interlock receptacle 208, the toe stop apparatus 202 is 
securely attached to the truck assembly 220. Preferably, either or both of 
the interlock member 206 or the portion of the truck members surrounding 
the interlock receptacle 208 are composed of a resilient compliant 
material in order to assure a relatively tight interlocking engagement 
therebetween. 
FIG. 20 illustrates still another alternate toe stop apparatus 222 having a 
separate interlock member 223 with an undercut edge portion 224 thereon, 
that is generally similar to the interlock member 206 and the undercut 
portion 210 shown in FIG. 19 and described above. The interlock member 222 
and the undercut edge portion 224 are adapted to be interlockingly and 
removably received within the above-described interlock receptacle 208 in 
the truck assembly 220. Instead of having an integral friction element, 
however, the interlock member 223 of the toe stop apparatus 222 includes a 
threaded aperture 226 therein for threadably receiving the threaded rod 
member 106 of the toe stop apparatus 102 shown in FIG. 2 and discussed 
above. Thus, either before or after the separate interlock member 223 is 
interlockingly attached to the truck assembly 220, the toe stop apparatus 
102 may be threadably rotated as described above in order to adjust the 
relative position between the friction element 104 and the interlock 
member 223. As described above, when the desired relative positon is 
obtained, the jam nut 110 is threadably tightened into engagement with the 
interlock member 223 in order to substantially fix the position of the 
friction element 204 relative to the truck assembly 220. It should be 
noted that the toe stop arrangements shown in FIGS. 2, 19 and 20 may be 
employed in conjunction with any of the embodiments of the invention shown 
and described herein. It should also be noted that such toe stop 
arrangements are equally applicable and adaptable to stop members located 
at other than toe or forward locations on the roller skate. 
The foregoing discussion discloses and describes exemplary embodiments of 
the present invention. One skilled in the art will readily rcognize from 
such discussion that various changes, modifications and variations may be 
made therein without departing from the spirit and scope of the invention 
as defined in the following claims.