US20010042966A1

US20010042966A1 - Wheeled skate device

Info

Publication number: US20010042966A1
Application number: US09/832,295
Authority: US
Inventors: Chien-Min Sung
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-04-07
Filing date: 2001-04-10
Publication date: 2001-11-22

Abstract

A wheeled skate device has a pair of large primary wheels coupled to opposite lateral sides of a platform. The primary wheels rotate about primary axes of rotation in both forward and rearward direction. The skate device may have a secondary wheel coupled to one end of the platform which rotates about a secondary axis of rotation. The secondary wheel also pivots about a vertical pivot axis through at least 180 degrees such that the secondary wheel turns with the platform without sliding on the support surface. The wheels cooperatively operate in a travel mode and spinning mode. In the travel mode, all the wheels rotate in the same direction to horizontally displace the platform. In the spinning mode, the primary wheels rotate opposite directions to one another, and the secondary axis of rotation is traverse to the primary axes of rotation. The platform also may pivot about the primary axes of rotation between a horizontal orientation and an inclined orientation. In the horizontal orientation, the secondary wheel is disposed above the support surface in a non-contacting relationship. In the inclined orientation, the secondary wheel makes rolling contact with the support surface.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 09/287,462 filed Apr. 7, 1999.[0001]

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a wheeled skate device. More particularly, the present invention relates to a wheeled skate device having a pair of large primary wheels mounted on opposite sides of the device, and a secondary wheel which pivots about a vertical axis in at least 180 degrees, such that the skate may roll forward on the wheels, or spin on the wheels while the wheels maintain rolling contact with the ground without sliding.

2. Prior Art

Conventional roller skates have two pairs of wheels, forward and back, mounted underneath a boot, or other foot platform, in two rows. More modern in-line skates have a plurality of wheels, typically four, mounted underneath the boot in a single row to imitate a blade of an ice skate. Because the wheels are mounted underneath the skate, the wheels must be kept relatively small in order to prevent raising the user's center of gravity, and thus making balance more difficult. Therefore, conventional and modern skates seldom use wheels larger than 6 cm in diameter.

One disadvantage with smaller wheels is that frictional forces are more difficult to overcome. The smaller wheels tend to get caught in irregularities, such as indentations, holes, cracks, roughness, etc., in the ground or support surface on which the wheels are rolling. Even smaller irregularities tend to catch, or drag, the small wheels.

Another disadvantage with the four-wheel design of conventional and modern skates is the difficulty in turning. The turning is made difficult with four wheels simultaneously touching the ground because of the frictional force of the four wheels. In addition, with four wheels located at four corners of the boot, as with conventional skates, or with four wheels located in a single line, as with modern in-line skates, the wheels must slide or drag on the ground or contact surface. The sliding or dragging of wheels consumes energy and the user loses speed when making a turn. In addition, balance is more difficult to maintain during sliding. Maneuverability is particularly difficult when making rapid sharp turns, such as when playing hockey. Other movements available in ice skating, such as spinning, are also prohibited by the frictional contact between the sliding wheels and the ground. Therefore, the skill of the user is often constrained by the limitations in the skate.

U.S. Pat. No. 4,541,643, issued Sep. 17, 1985 to Pavincic, discloses a two-wheeled skate device having two large wheels arranged on opposite sides of a frame. One disadvantage with this type of skate device is that the wheels are unidirectional, or rotate in only one direction. Thus, the skates may roll in one direction, such as forwardly, but may not spin, or have the wheels rotate in opposite directions.

U.S. Pat. No. 4,844,491, issued Jul. 4, 1989, to Wheelwright, discloses a wheeled skate device with three wheels. Two large rear wheels are arranged on opposite sides of a platform, and another large front wheel is arranged at the front. One disadvantage with this type of skate is that the three wheels, like the four wheels of conventional and in-line skates, are generally fixed in a single direction. Thus, the skate is prevented from spinning because the front wheel would drag on the ground.

Therefore, it would be advantageous to develop a wheeled skating device capable of performing more like ice skates. It would also be advantageous to develop a wheeled skate device capable of reducing friction losses. In addition, it would be advantageous to develop a wheeled skate device capable of making turns without sliding the wheels on the ground. In addition, it would be advantageous to develop a wheeled skate device capable of providing greater stability and balance.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the present invention to provide a wheeled skate device for enhancing the user's performance and expanding the user's ability to turn and maneuver.

It is another object of the present invention to provide a wheeled skate device for reducing frictional losses.

It is yet another object of the present invention to provide a wheeled skate device capable of providing other actions, such as spinning.

It is a further object of the present invention to provide a wheeled skate device with greater stability and balance.

These and other objects and advantages of the present invention are realized in a wheeled skate device having a pair of primary wheels each rotatably coupled to different lateral sides of a platform. The platform is configured for being movably disposed over a support surface, such as the ground, and is configured for receiving a foot of a user. The platform has opposite lateral sides, such as left and right sides perpendicular to the general direction of travel, and opposite longitudinal ends, such as front and back ends along the general direction of travel. The primary wheels are configured for rolling disposition on the support surface, and are bi-directionally rotatable about primary axes of rotation, or rotate in forward and backward directions.

The primary wheels maintain the platform at a specified height above the support surface. Preferably, the primary wheels are coupled to the platform outside an outer perimeter of the platform. In addition, the primary wheels preferably have an outer diameter greater than the specified height. Thus, the primary wheels advantageously reduce friction.

The primary wheels are configured for cooperatively operating in at least two modes to make rolling contact with the support surface without sliding. The two modes include a travel mode and a spinning mode. In the travel mode, the primary wheels each rotate in a common forward, or backward, direction. In the spinning mode, the primary wheels rotate in opposite directions relative to one another.

In accordance with one aspect of the present invention, a secondary wheel may be rotatably coupled to one end of the platform, and be configured for rolling contact with the support surface. The secondary wheel rotates about a secondary axis of rotation which is oriented generally horizontally. The secondary wheel further pivots about a generally vertical pivot axis through an angular range of at least 180 degrees. Thus, the secondary wheel advantageously pivots as the platform turns without sliding or dragging on the support surface.

In addition, the primary and secondary wheels are configured for cooperatively operating in the travel and spinning modes. In the travel mode, the primary and secondary wheels each rotate in a common forward, or backward, direction. In the spinning mode, the secondary axis of rotation of the secondary wheel is oriented traverse to the primary axes of rotation of the primary wheels.

In accordance with another aspect of the present invention, the platform may vertically pivot about the primary axis of rotation between a first generally horizontal orientation and a second inclined orientation. In the first generally horizontal orientation, the secondary wheel is in a non-contacting relationship with the support surface. Thus, the skate device has only two points of contact with the support surface which are defined by the primary wheels. In the second inclined orientation, the secondary wheel contacts the support surface. Thus, the skate device has only three points of contact with the support surface which are defined by the primary and secondary wheels.

These and other objects, features, advantages and alternative aspects of the present invention will become apparent to those skilled in the art from a consideration of the following detailed description taken in combination with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a preferred embodiment of a wheeled skate device of the present invention in a first horizontal orientation. [0022]
FIG. 2 is an end elevational view of the preferred embodiment of the wheeled skate device of the present invention. [0023]
FIG. 3 is a top schematic view of the preferred embodiment of the wheeled skated device of the present invention showing spinning movement of the device. [0024]
FIG. 4 is a side elevational view of the preferred embodiment of the wheeled skate device of the present invention in a second inclined orientation. [0025]
FIG. 5[0026] a is a cross sectional side view of the preferred embodiment of a secondary wheel of the wheeled skate device of the present invention.
FIG. 5[0027] b is a bottom view of the preferred embodiment of the secondary wheel of the wheeled skate device of the present invention.
FIG. 6[0028] a is a side elevational view of an alternative embodiment of a secondary wheel of the wheeled skate device of the present invention.
FIG. 6[0029] b is a bottom view of the alternative embodiment of the secondary wheel of the wheeled skate device of the present invention.
FIG. 7 is an end elevational view of an alternative embodiment of a wheeled skate device of the present invention. [0030]
FIG. 8 is an end elevational view of an alternative embodiment of a wheeled skate device of the present invention. [0031]
FIG. 9 is a side elevational view of an alternative embodiment of a wheeled skate device of the present invention. [0032]
FIG. 10 is a side elevational view of an alternative embodiment of a wheeled skate device of the present invention. [0033]
FIG. 11 is a side elevational view of an alternative embodiment of a wheeled skate device of the present invention. [0034]
FIG. 12 is a side elevational view of an alternative embodiment of a wheeled skate device of the present invention. [0035]
FIG. 13[0036] a is a top schematic view of the wheels of a conventional prior art skate.
FIG. 13[0037] b is a top schematic view of the wheels of a prior art in-line skate.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made to the drawings in which the various elements of the present invention will be given numerical designations and in which the invention will be discussed so as to enable one skilled in the art to make and use the invention. [0038]
As illustrated in FIGS. 1 and 2, a wheeled skate device, indicated generally at [0039] 10, is shown disposed on the ground or a support surface 14. The support surface 14 may be a concrete sidewalk or driveway, an asphalt road or street, a wooden roller skating rink, etc. The skate device 10 has a platform 18 which is configured to receive and securely hold a user's foot, or other limb, such as a user's knee. The platform 18 may be part of a boot 22 which is sized and shaped to receive a user's foot, as shown, or may be configured to receive a boot.
The [0040] platform 18 is movably disposed above the support surface 14, and moves over the support surface 14 as the skate device 10 rolls on the support surface. In addition, the platform 18 is disposed over the support surface 14 at a specified height, defining a space between the platform 18 and the support surface 14.
The [0041] platform 18 may be generally flat, as shown, and has an outer perimeter 26 which defines the outer edge of the platform, and which may be sized and shaped as the user's foot or shoe. The platform also has opposite lateral sides, including a first left side 30 and a second right side 32 perpendicular to the general direction of travel, and opposite longitudinal ends, including a forward end 36 and a rearward end 38 along the general direction of travel. It is of course understood that the skate device 10 represents one of a pair of skate devices which each would be worn on a separate foot of a user. As such, the lateral sides may represent an inside edge facing opposite an adjacent skate, or an outside edge.
The [0042] skate device 10 further includes a pair of primary wheels, including a first or left primary wheel 42, and a second or right primary wheel 44 (FIG. 3), each rotatably coupled to different lateral sides 30 and 32 of the platform 18. Thus, the left primary wheel 42 is rotatably coupled to the left side 30, while the right primary wheel 44 is rotatably coupled to the right side 32. The primary wheels 42 and 44 make rolling contact with the support surface 14 and support or maintain the platform 18 at the specified height above the support surface 14.
In the preferred embodiment, the [0043] primary wheels 42 and 44 rotate about a common, primary axis of rotation 48. The wheels preferably are bi-directional, or rotate in both forward and backward directions about the axis of rotation 48. The primary wheels 42 and 44 may share a common axle 52, which is co-axial with the primary axis of rotation 48. The primary wheels 42 and 44 may rotate about the axle 52, or may be fixed to the axle 52 with the axle 52 rotating with respect to the platform 18.
In the preferred embodiment, the [0044] primary wheels 42 and 44 advantageously are relatively large, or have an outer diameter which is greater than the specified height between the platform 18 and support surface 14. One advantage of the large size of the primary wheels 42 and 44 is the reduction in friction between the wheels and the support surface. In addition, the large wheels are less likely to become stuck or caught in irregularities in the support surface. The outer diameter of the wheels may be as large as 30 cm, or even larger.
The [0045] primary wheels 42 and 44 preferably are coupled to the sides 30 and 32 of the platform outside the outer perimeter 26 of the platform 18. Thus, the large size of the primary wheels 42 and 44 does not raise the user's center of gravity, and thus makes balance easier. In addition, locating the primary wheels 42 and 44 outside the outer perimeter 26 may even lower the center of gravity, as discussed more fully below.
The primary axis of [0046] rotation 48, and the axle 52, are preferably disposed at a height above the ground at least as high as the platform 18, or lower surface of the platform, as shown. The axle 52, and the primary axis of rotation 48, may pass through, or below, the platform 18, or lower surface. Thus, the axle 52 may provide support for the platform 18 between the wheels 42 and 44.
The [0047] primary wheels 42 and 44, or the axle 52 and primary axis of rotation 48, may be located at, or on a direct vertical line from, a center of gravity of the user, indicated by line 56. Thus, the user may balance only on the primary wheels, and travel and/or spin on only the two primary wheels.
The [0048] skate device 10 may further include a secondary wheel 60 rotatably coupled at one end of the platform 18. Preferably, the primary wheels 42 and 44 are located closer to the rear end 38 of the platform 18 than to the front end 36, and the secondary wheel 60 is located closer to the front end 36 than to the rear end 38. The secondary wheel 60 preferably has an outer diameter less than the specified height and is disposed under the platform 18, or within the outer perimeter 26 of the platform 18. Thus, the secondary wheel 60 does not protrude from the platform 18 to create a skate which is longer than necessary, and which may interfere with a mating skate or other structures. It is of course understood that the secondary wheel 60 may comprise two secondary wheels.
The [0049] secondary wheel 60 rotates about a secondary axis of rotation, indicated at 64. The secondary axis of rotation 64 preferably is located between the platform 18 and the support surface 14 such that the secondary wheel 60 does not protrude from the platform 18. In addition, the secondary axis of rotation 64 is oriented generally horizontally, or is disposed in a generally horizontal plane parallel with the support surface 14, and/or the platform 18.
The [0050] secondary wheel 60 also advantageously pivots about a generally vertical pivot axis, indicated at 68, and pivots through an angular range of at least 180 degrees. The secondary wheel 60 may turn, or pivot, as the skate device 10 turns. Thus, the skate device 10, or platform 18, may turn without any of the wheels 42, 44 or 60 sliding on the support surface 14. The 180 degree angular range allows the secondary wheel 60 to pivot 90 degrees in either direction, left or right, so that the skate may turn, or even spin, in either direction. In addition, the secondary wheel 60 preferably freely pivots about the pivot axis 68, or pivots without hindrance, so that the skate device 10 may be easily turned.
The [0051] primary wheels 42 and 44, and the secondary wheel 60, operate cooperatively to roll on the contact surface 14 without sliding. By rolling, rather than sliding, friction between the wheels 42, 44 and 60 and support surface 14 is reduced. In addition, the wheels 42, 44 and 60 operate in at least two modes, including a travel mode and a spinning mode. In the travel mode, all of the wheels 42, 44 and 60 rotate in a common direction, such as forward or backward, and the platform 18 is horizontally displaced. In addition, the primary and secondary axes of rotation 48 and 64 are parallel. Referring also to FIG. 3, in the spinning mode, the primary wheels 42 and 44 rotate in opposite directions relative to one another. For example, the left wheel 42 may rotate in a forward direction, while the right wheel 44 may rotate in a rearward direction. The secondary wheel 60 rotates about the secondary axis of rotation 64, which is oriented traverse to, or intersects, the primary axis 48. Thus, the secondary wheel 60 turns or pivots about the vertical pivot axis 68 so that the secondary wheel 60 rolls, rather than slides, and may travel around the primary wheels about a vertical axis. In the spinning mode, the platform 18 pivots about a vertical axis, and may pivot about the vertical line from the center of gravity 56. As shown in FIG. 3, the secondary wheel 60 turns to travel in the direction of rotation, indicated at 70. Thus, the user may engage in spinning and other skating maneuvers previously unattainable with prior art skates. This represents a significant advantage over prior art skates in which the wheels do not turn in the direction of the turn, and thus slide on the ground, as shown in FIG. 13a for conventional skates, and FIG. 13b for in-line skates.
Referring to FIGS. 1 and 3, the [0052] primary wheels 42 and 44 preferable rotate about the common primary axis of rotation 48. In addition, the platform preferably and advantageously vertically pivots about the primary axis 48 between a first generally horizontal orientation, as shown in FIG. 1, and a second inclined or tilted orientation, as shown in FIG. 4. Referring to FIG. 1, in the first horizontal orientation the secondary wheel 60 is in a non-contacting relationship with the support surface 14, or is suspended above the support surface. Thus, the skate device 10 has only two points of contact with the support surface 14 at a given time defined by the two primary wheels 42 and 44. The first orientation may be used for travel, with only the primary wheels rolling on the support surface and the user balancing on the primary axis. The first orientation may also be used in the spinning mode because the skate device is easier to turn with only two points of contact. With only two points of contact, the skate device has reduced frictional losses and is easier to turn. Thus, the secondary wheel 60 may be used only intermittently.
Referring to FIG. 4, in the second inclined orientation, the [0053] secondary wheel 60 is in rolling contact with the support surface 14. Thus, the skate device 10 has only three points of contact with the support surface 14 at a given time defined by the two primary wheels 42 and 44 and the single secondary wheel 60. The second orientation may be used to help maintain the user's balance, at slower speeds, etc. Thus, the user may travel by balancing on only the primary wheels, or may travel resting on all three wheels. It is of course understood that all three wheels may be configured to contact the ground continuously, and that two or more secondary wheels may be provided resulting in four or more points of contact.
Referring to FIGS. 5[0054] a and 5 b, the secondary wheel 60 may comprise a spherical ball 72 coupled to the platform 18 by a coupling member 74. The coupling member 74 is secured to the platform 18, and defines a semi-spherical cavity 78 therein and a circular opening 82 in the lower side of the coupling member and extending into the cavity 78. Thus, the cavity 78 and opening 82 of the coupling member 74 face downwardly, or towards the support surface 14. The spherical ball 72 is rotatably disposed in the semi-spherical cavity 78 and a portion 86 of the ball 72 protrudes from the cavity 78 and opening 82 to contact the support surface 14. In addition, a plurality of bearings 88 may be disposed in the cavity 78 between the coupling member 74 and the ball 72 to reduce friction. Alternatively, any low friction surfaces or materials may be used. The semi-spherical cavity 78 allows the spherical ball 72 to rotate about the axis of rotation 64, and to pivot about the pivot axis 68.
Referring to FIGS. 6[0055] a and 6 b, the secondary wheel 60 may comprise a pivotal coupler, indicated generally at 92, pivotally and rotatably coupling a wheel 94 to the platform 18. The pivotal coupler 92 includes an arm 96 with a first end 98 and a second end 100. The wheel 94 is rotatably coupled to the first end 98 of the arm 96. The pivotal coupler 92 also includes a pivot base 102 attached to the platform 18. The second end 100 of the arm 96 is pivotally coupled to the pivot base 102. Thus, the arm 96, and the wheel 94, pivot with respect to the pivot base 102 about the pivot axis 68. The arm 96 is preferably coupled to the pivot base 102, and the wheel 94, at an angle with respect to the vertical. Thus, as the platform 18 is turned, the arm 96 and wheel 94 tend to pivot about the pivot axis 68 so the wheel 94 rolls in the direction of the turn. Therefore, the wheel 94 maintains rolling contact with the support surface 14 without sliding.
As indicated above, the primary axis of [0056] rotation 48 is preferably located at a height at least as high as the specified distance of the platform 18 from the support surface 14. By locating the axis of rotation 48 at, or above, the platform 18, the platform 18 is maintained closer to the support surface 14, the center of gravity of the user is kept lower, and thus, balance is easier to maintain. In addition, by locating the axis of rotation 48 higher, and locating the wheels 42 and 44 outside the outer perimeter 26 of the platform 18, larger wheels 42 and 44 may be used, or the diameter of the wheels 42 and 44 may be increased. Larger wheels help reduce friction and decrease the likelihood of the wheels being caught on irregularities in the support surface.
In order to increase the diameter of the [0057] wheels 42 and 44, and keep the center of gravity of the user lower, it may be necessary to raise the axis of rotation 48. Referring to FIG. 7, the axis of rotation 48 has been raised above the platform 18, or has been located at a height greater than the specified distance of the platform 18 from the support surface 14. In this case, the wheels 42 and 44, or axle 52, are coupled to lateral arms 120 and 122, respectively, which are attached to, and extend upwardly from, the platform 18. Thus, the lateral arms 120 and 122 and platform 18 form a U-shaped member for supporting the wheels 42 and 44. In the embodiment of FIG. 7, the outer diameter of the wheels 42 and 44 may be increased without raising the center of gravity of the user, thus reducing friction and increasing balance.
Referring to FIG. 8, the axis of [0058] rotation 48 has been raised even further. The boot 22 has a forefoot portion or section 130 with an upper surface 132. The axis of rotation 48 is disposed at, or above, the upper surface 132 of the forefoot portion 130. The wheels 42 and 44, or axis 52, are coupled to a horizontal member 134 disposed above and parallel to the platform 18. The horizontal member 134 may be attached to lateral arms 120 and 122 as described above. The horizontal member 134, lateral arms 120 and 122, and platform 18 form a loop support member. In the embodiment of FIG. 8, the outer diameter of the wheels 42 and 44 may be increased even further. It is of course understood that the axis of rotation may be raised even higher above the upper surface of the forefoot portion.
As illustrated in FIG. 1, and as described above, the [0059] secondary wheel 60 may be located at the front end 36 of the platform 18, while the primary wheels 42 and 44 are located at the center of gravity 56 and closer to the second end 38. The wheels 42, 44 and 60 may be located and arranged to suit the particular needs of the user. Referring to FIG. 9, the secondary wheel 60 alternatively may be located at the rear end 38 of the platform 18, while the primary wheels 42 and 44 may be located more forwardly. The embodiment of FIG. 1 may be more comfortable for users who prefer to lean forward to rest on all three wheels, while the embodiment of FIG. 9 may be more comfortable for users who prefer to lean backward to rest on all three wheels. Referring to FIG. 10, the skate device 10 also may include a second secondary wheel 136. Thus, the first secondary wheel 60 may be located at the front end 36, while the second secondary wheel 136 may be located at the rear end 38. Such a configuration may be useful to help maintain balance in either direction.
As described and illustrated above, the [0060] primary wheels 42 and 44 may share a common primary axis of rotation 48 which allows the platform 18 to vertically pivot. Referring to FIG. 11, the primary wheels 140 and 142 may have different primary axes of rotation 144 and 146, respectively. The axes of rotation 144 and 146 are parallel, but spaced at different locations along the length of the platform 18. Thus, the wheels 140 and 142 are spaced at different location along the length of the platform 18. Spacing the wheels 140 and 142 at different locations may make balance easier for the user. Rather than balancing along a single axis 48 (FIG. 1), the user may balance along two axes 144 and 146.
In addition, the [0061] primary wheels 140 and 142 may have different outer diameters, as shown in FIG. 11. The different diameters may provide different turning characteristics.
Referring to FIG. 12, the [0062] skate device 10 also may have wheel covers 150 disposed over the wheels 42 and 44 to prevent the wheels 42 and 44 from spraying water and/or rocks. In addition, the wheel covers 150 also prevent adjacent wheels, such as the inside wheels of a pair of skates, from abutting one another.
Referring to FIG. 1, the [0063] skate device 10 also may have a brake member 160 attached to the rear end 38 of the platform 18 or boot 22. The brake member 160 may be pivoted into contact with the ground 14 by the user leaning backwards.
It is to be understood that the described embodiments of the invention are illustrative only, and that modifications thereof may occur to those skilled in the art. Accordingly, this invention is not to be regarded as limited to the embodiments disclosed, but is to be limited only as defined by the appended claims herein. [0064]

Claims

What is claimed is:

1. A wheeled skate device comprising:

a platform configured for being movably disposed over a support surface and configured for receiving a foot of a user, the platform having opposite lateral sides and opposite longitudinal ends; and

a pair of primary wheels each rotatably coupled to different lateral sides of the platform, the primary wheels being configured for rolling disposition on the support surface and being bi-directionally rotatable about primary axes of rotation; and

wherein the primary wheels are configured for cooperatively operating in at least two modes to make rolling contact with the support surface without sliding, the two modes including (i) a travel mode in which the primary wheels each rotate in a common direction, and (ii) a spinning mode in which the primary wheels rotate in opposite directions relative to one another.

2. The skate device of

claim 1

, further comprising:

a secondary wheel rotatably coupled to one end of the platform and configured for rolling contact with the support surface, the secondary wheel rotating about a secondary axis of rotation which is oriented generally horizontally, the secondary wheel further pivoting about a generally vertical pivot axis through an angular range of at least 180 degrees, and

wherein the primary and secondary wheel cooperatively operate in the travel and spinning modes, such that the primary and secondary wheels each rotate in a common direction in the travel mode, and such that the secondary axis of rotation of the secondary wheel is oriented traverse to the primary axes of rotation of the primary wheels in the spinning mode.

3. The skate device of

claim 2

, wherein the primary wheels have a common primary axis of rotation, and wherein the platform vertically pivots about the primary axis of rotation between (i) a first generally horizontal orientation in which the secondary wheel is in a non-contacting relationship with the support surface, and such that the skate device has only two points of contact with the support surface defined by the primary wheels, and (ii) a second inclined orientation in which the secondary wheel contacts the support surface, and such that the skate device has only three points of contact with the support surface defined by the primary and secondary wheels.

4. The skate device of

claim 3

, wherein the secondary wheel has an outer diameter which is less than a distance between the support surface and the platform when the platform is in the first generally horizontal orientation.

5. The skate device of

claim 2

, wherein the platform is configured for being movably disposed above a support surface at a specified height and defining a space between the platform and the support surface; and wherein the primary wheels are configured for maintaining the support surface at the specified height, each primary wheel having an outer diameter greater than the specified height.

6. The skate device of

claim 5

, wherein the secondary wheel has an outer diameter less than the specified height.

7. The skate device of

claim 1

, wherein the platform has a lower surface configured for facing the support surface; and wherein the primary axes of rotation of the primary wheels are disposed at a height with respect to the support surface at least as high as the lower surface of the platform.

8. The skate device of

claim 1

, wherein the primary wheels are located at a center of gravity of the user.

9. The skate device of

claim 2

, wherein the ends of the platform define front and rear ends, wherein the primary wheels are located closer to the rear end of the platform than the secondary wheel, and wherein the secondary wheel is located closer to the front end than to the rear end.

10. The skate device of

claim 2

, wherein the ends of the platform define front and rear ends, wherein the primary wheels are located closer to the front end of the platform than the secondary wheel, and wherein the secondary wheel is located closer to the rear end than to the front end.

11. The skate device of

claim 2

, wherein the secondary wheel is a first secondary wheel disposed at one end of the platform; and further comprising a second secondary wheel disposed at the other end of the platform.

12. The skate device of

claim 2

, wherein the secondary wheel comprises a spherical ball rotatably disposed in a semi-spherical cavity defined by a coupling member attached to the platform such that a portion of the spherical ball protrudes from the cavity of the coupling member and contacts the support surface.

13. The skate device of

claim 2

, further comprising a pivotal coupler having a first end rotatably coupled to the secondary wheel, and a second end pivotally coupled to the platform and pivoting about the vertical pivot axis.

14. The skate device of

claim 1

, further comprising a boot configured for receiving a user's foot attached to the platform, the boot having a forefoot section with an upper surface, and wherein the primary axes of rotation of the primary wheels are disposed at or above the upper surface of the boot.

15. The skate device of

claim 1

, wherein the primary wheels have separate axes of rotation which are parallel with respect to one another.

16. The skate device of

claim 1

, wherein the platform has a length, and wherein the primary wheels are coupled to the platform at different locations along the length of the platform.

17. The skate device of

claim 1

, wherein the primary wheels have different diameters.

18. The skate device of

claim 1

, further comprising a pair of covers, each disposed over an upper portion of one of the primary wheels.

19. The skate device of

claim 1

, further comprising a brake member attached to the platform.

20. A wheeled skate device comprising:

a platform configured for being movably disposed above a support surface at a specified height and defining a space between the platform and the support surface, the platform further being configured for receiving a foot of a user, the platform having an outer perimeter, opposite lateral sides and opposite longitudinal ends;

a pair of primary wheels each rotatably coupled to different lateral sides of the platform outside the outer perimeter of the platform, the primary wheels being configured for rolling disposition on the support surface and being configured for maintaining the platform at the specified height, and the primary wheels further having an outer diameter greater than the specified height and being bi-directionally rotatable about primary axes of rotation; and

wherein the primary and secondary wheels are configured for cooperatively operating in at least two modes to make rolling contact with the support surface without sliding, the two modes including (i) a travel mode in which the primary and secondary wheels each rotate in generally the same direction to horizontally displace the platform, and (ii) a spinning mode in which the primary wheels rotate in opposite directions relative to one another, and in which the secondary axis of rotation of the secondary wheel is oriented traverse to the primary axes of rotation of the primary wheels, to pivot the platform about a vertical axis.

21. The skate device of

claim 20

22. The skate device of

claim 21

23. The skate device of

claim 20

24. The skate device of

claim 20

, wherein the platform has a lower surface configured for facing the support surface; and wherein the primary axes of rotation of the primary wheels are coupled to the platform at a height with respect to the support surface at least as high as the lower surface of the platform.

25. The skate device of

claim 20

, wherein the primary wheels are located at a center of gravity of the user.

26. The skate device of

claim 20

27. The skate device of

claim 20

28. The skate device of

claim 20

29. The skate device of

claim 20

, wherein the secondary wheel comprises a spherical ball rotatably dispose in a semi-spherical cavity defined by a coupling member attached to the platform such that a portion of the spherical ball protrudes from the cavity of the coupling member to contact the support surface.

30. The skate device of

claim 20

31. The skate device of

claim 20

32. The skate device of

claim 20

33. The skate device of

claim 20

34. The skate device of

claim 20

, wherein the primary wheels have different diameters.

35. The skate device of

claim 20

36. The skate device of

claim 20

, further comprising a brake member attached to the platform.

37. A wheeled skate device comprising:

a pair of primary wheels each rotatably coupled to different lateral sides of the platform outside the outer perimeter of the platform, the primary wheels being configured for rolling disposition on the support surface and being configured for maintaining the platform at the specified height, and the primary wheels further having an outer diameter greater than the specified height and being bi-directionally rotatable about a common primary axis of rotation; and

a secondary wheel rotatably coupled to one end of the platform and configured for disposition between the platform and support surface and configured for rolling contact with the support surface, the secondary wheel having an outer diameter less than the specified height and rotating about a secondary axis of rotation which is oriented generally horizontally, the secondary wheel further pivoting about a generally vertical pivot axis through an angular range of at least 180 degrees, and

wherein the primary and secondary wheels are configured for cooperatively operating in at least two modes to make rolling contact with the support surface without sliding, the two modes including (i) a travel mode in which the primary and secondary wheels each rotate in generally the same direction to horizontally displace the platform, and (ii) a spinning mode in which the primary wheels rotate in opposite directions relative to one another, and in which the secondary axis of rotation of the secondary wheel is oriented traverse to the primary axis of rotation of the primary wheels, to pivot the platform about a vertical axis, and

wherein the platform vertically pivots about the primary axis of rotation of the primary wheels between (i) a first generally horizontal orientation in which the secondary wheel is in a non-contacting relationship with the support surface, and such that the skate device has only two points of contact with the support surface defined by the primary wheels, and (ii) a second inclined orientation in which the secondary wheel contacts the support surface, and such that the skate device has only three points of contact with the support surface defined by the primary and secondary wheels.