Patent ID: 8181992

Claim:
A powered vehicle comprising: a frame; a seat mounted on the frame; a pair of drive wheels positioned on opposing sides of the frame; a drive motor assembly operatively coupled to at least one of the drive wheels for powering rotation of the drive wheel about a drive wheel axis and for powering movement of the vehicle across a ground plane; at least one anti-tip assembly comprising a suspension arm pivotably mounted to the frame at a suspension arm pivot axis, said suspension arm extending from said suspension arm pivot axis outwardly from the frame, said suspension arm pivot axis vertically spaced above the ground plane, and an anti-tip wheel having a rotational axis about which the anti-tip wheel rotates, said anti-tip wheel disposed on the extended suspension arm, the vertical position of the suspension arm pivot axis with respect to the ground plane in normal operation being spaced from and positioned relatively below a line drawn between the drive wheel axis and the rotational axis of the anti-tip wheel; and a resilient link operatively connecting the drive motor assembly to the suspension arm, wherein, in response to torque created by the motor in rotating the drive wheel, the drive motor assembly pivots and causes, through the operative connection of the resilient link, the suspension arm to pivot about the suspension arm pivot axis, and a responding vertical movement of the anti-tip wheel.