Patent ID: 6053227
Filing Date: 2000-04-25
Classification: B60B,B60C

Abstract:
A traction device for attachment with respect to a tire rotating on an axis, the tire having a terrain engaging surface connecting a pair of sidewalls, said traction device comprising:a plurality of arms adapted to extend radially with respect to the axis, each of said plurality of arms including a first section adapted to be radially extensible with respect to the terrain engaging surface and a second section adapted to be extensible across the terrain engaging surface, each of said plurality of second sections being mounted at a radially outward end of a corresponding one of said plurality of first sections;a plurality of fingers adapted to engage one of the pair of sidewalls, each of said plurality of second sections extensibly connecting a corresponding one of said plurality of first sections and a corresponding one of said plurality of fingers;a winch including a cable drum and a plurality of cables, each of said plurality of cables extending from a corresponding one of said plurality of fingers, along corresponding ones of said first and second sections, to said cable drum;a plurality of first springs each expanding a corresponding one of said first sections; anda plurality of second springs each expanding a corresponding one of said second sections;wherein each of said first springs has a lower spring constant than a corresponding one of said plurality of second springs.