A wheel assembly for a roller skate. The wheel assembly mainly includes a pivotal seat, a singular locking member and a wheel set. The pivotal seat includes a first end pivotally connected to a sole base by a mounting member for convertibly moving between a stowed position and an extended position and...http://www.google.co.uk/patents/US6523836?utm_source=gb-gplus-sharePatent US6523836 - Wheel assembly for roller skate
