Patent ID: 8690171

Claim:
A working vehicle having a pair of drive wheels for dual path steering and at least one caster wheel being part of a castor wheel assembly selectively providing steering assist to the drive wheels, the caster wheel assembly comprising: a pivoting shaft coupled with a caster wheel; an engagement lug connected to the shaft in a fixed manner such that the engagement lug pivots with the shaft; a steering arm selectively engagable with the engagement lug, said steering arm having an aperture formed therein configured to receive the engagement lug such that when the engagement lug is received in the aperture, the steering arm and engagement lug are coupled together and pivoting motion of the steering arm is transferred to the engagement lug; a turn assist cylinder connected to an outward end of the steering arm; an engagement mechanism acting upon the steering arm for engaging the steering arm with the engagement lug, the engagement mechanism having an engaged position and a disengaged position, wherein in one of the engaged and disengaged positions the steering arm is coupled with the engagement lug such that the turn assist cylinder pivots the shaft and caster wheel, and in the other of the engaged and disengaged position, the steering arm is uncoupled with the engagement lug such that the shaft and caster wheel are free to pivot independent of the turn assist cylinder; and a locking cylinder connected to the engagement mechanism configured to move the engagement mechanism between the engaged position and the disengaged position.