Patent ID: 7566102

Claim:
A wheel rotatable about a main axis, including: (a) a frame including a plurality of supports; (b) at least two series of rollers, the first of said series of rollers aligned with a first plane normal to said main axis and spaced to form a first discontinuous rim; and (c) the second of said series of rollers radially spaced from the main axis and aligned with a second plane normal to said main axis, said second series of rollers spaced to form a second discontinuous rim, said first and second planes aligned parallel to and spaced from one another, each roller of said first and said second series of rollers being: (i) radially spaced from said main axis; (ii) rotatable about an axis normal to said main axis; (iii) mounted between a pair of said supports; and (iv) having a lateral central cross-sectional diameter greater than the diameter of its end portions, whereby, when viewed in side elevation, the effective ground contacting surface of each said roller of said first series of rollers overlaps with the effective ground contacting surface of at least one diagonally adjacent roller of said second series of rollers so that said wheel is adapted to make effective ground contact through at least two of said rollers at any one time for effective travel in directions having a component parallel to said main axis, wherein each roller of said first series of rollers is mounted on a continuous polyaxle ring, each roller axle length of said polyaxle ring having a linear axis and integrally formed with adjacent other axle lengths and extending between and through a first series of said supports.