A wheel assembly apparatus is disclosed. In at least one embodiment, a wheel hub is coaxially positionable within a wheel. A first bearing and a laterally opposed second bearing are each positionable coaxially within the wheel hub, with an inner race of the first bearing being laterally spaced apart from an opposing inner race of the second bearing so as to form a bearing gap therebetween. A first outer spacer is positionable in contact with an outer race of the first bearing, and a second outer spacer is positionable in contact with an outer race of the second bearing. Accordingly, an axle is capable of extending coaxially through each of the first outer spacer, first bearing, second bearing, second outer spacer, wheel hub and wheel, thereby enabling the wheel to rotate about the axle.

An electric roller skate system includes a pair of roller skates, where each of the pair of roller skates includes: a base configured to receive a foot of a rider, where the base comprises a front base and a rear base, where a distance between the front base and the rear base is adjustable; a front main body attached to the front base; a rear main body attached to the rear base; an ankle strap attached to the rear main body; two front wheels attached to a bottom of the front base; a rear wheel attached to a bottom of the rear base, where a cross-section of the rear wheel has a barrel shape; a battery; and an electric motor mechanically coupled to the rear wheel.

An electric roller skate system includes a pair of roller skates, where each of the pair of roller skates includes: a base configured to receive a foot of a rider, where the base comprises a front base and a rear base, where a distance between the front base and the rear base is adjustable; a front main body attached to the front base; a rear main body attached to the rear base; an ankle strap attached to the rear main body; two front wheels attached to a bottom of the front base; a rear wheel attached to a bottom of the rear base, where a cross-section of the rear wheel has a barrel shape; a battery; and an electric motor mechanically coupled to the rear wheel.

An inline wheeled truck is a structural arrangement for wheels on a skating device. The inline wheeled truck includes a first wheel, a second wheel, a left elongated bracket, a right elongated bracket, a cross platform, a base platform, a first support member, and a second support member. The first wheel and the second wheel allows the inline wheeled truck to roll in a forward direction and a backward direction. The left elongated bracket and the right elongated bracket evenly space and structurally secure the first wheel and the second wheel. The cross platform structurally bridges the left elongated bracket and the right elongated bracket. The first support member and the second support member are connected in between the cross platform and the base platform and convert a tilting motion of the base platform into a steering motion of the cross platform.

A wearable motorized device comprising a shoe bracket, which can be fastened to a shoe; wheels that are installed on the left and right sides of the shoe bracket in parallel to support the wearer's lateral skating and longitudinal walking; a driving motor for rotationally driving the wheels; and a battery pack for powering the driving motor. The wheels are not coaxially installed on the two sides of the shoe bracket to drive the wearer's longitudinal skating, but instead are installed on the two sides of the shoe bracket in parallel to drive the wearer's lateral skating; the wearer can position his/her legs apart during skating, so the skating stability is improved. Its general contour does not significantly exceed the contour of the shoe in the longitudinal direction, thus and it will not strain the wearer when ascending or descending stairs.

The system disclosed and claimed herein is an electric propelling wheel and battery/motor control subsystem enabling the retrofitting of a standard skateboard, having standard truck and wheels, with electrical propulsion capabilities.

An electric vehicle may comprise a board including first and second deck portions each configured to receive a left or right foot of a ride, a wheel assembly disposed between the deck portions and including a ground-contacting element, a motor assembly mounted to the board and configured to rotate the ground-contacting element around an axle to propel the electric vehicle, at least one sensor configured to measure orientation information of the board, and a motor controller configured to receive orientation information measured by the sensor and to cause the motor assembly to propel the electric vehicle based on the orientation information. The electric vehicle may include exactly one ground-contacting element, and the motor may be a hub motor.

A roller includes a rim assembly and a tire assembly. The tire assembly includes a support ring and a tire mounted at the periphery of the support ring. The support ring and the rim assembly are detachably connected by a buckle structure. The buckle structure includes a plurality of elastic accommodating parts disposed on the inner side of the supporting ring, and a plurality of buckling parts disposed at the rim assembly. The elastic accommodating parts and the buckling parts are detachably connected. The elastic accommodating parts protrude out of the inner side of the support ring, and two ends of each elastic accommodating part are separately provided with a protruding first limiting block and a protruding second limiting block. The buckling parts are limited by the first limiting blocks and the second limiting blocks. The rim assembly and the tire assembly of the roller are detachably connected.

A roller includes a rim assembly and a tire assembly. The tire assembly includes a support ring and a tire mounted at the periphery of the support ring. The support ring and the rim assembly are detachably connected by a buckle structure. The buckle structure includes a plurality of elastic accommodating parts disposed on the inner side of the supporting ring, and a plurality of buckling parts disposed at the rim assembly. The elastic accommodating parts and the buckling parts are detachably connected. The elastic accommodating parts protrude out of the inner side of the support ring, and two ends of each elastic accommodating part are separately provided with a protruding first limiting block and a protruding second limiting block. The buckling parts are limited by the first limiting blocks and the second limiting blocks. The rim assembly and the tire assembly of the roller are detachably connected.

A wearable device configured to selectively provide roller transportation, the wearable device including a shoe, a plurality of wheel assemblies, each wheel assembly being configured to selectively roll relative to a ground surface about an associated axis of rotation, and a frame connected between the wheel assemblies, the frame comprising a trunk and a plurality of branches extending from the trunk, each of the branches being configured for connection to at least one of the plurality of wheel assemblies, wherein at least a portion of the shoe is located vertically higher than at least a portion of the frame when at least one of the wheel assemblies is in contact with the ground surface and the at least one of the wheel assemblies is positioned to selectively roll relative to the ground surface.