Patent ID: 7168717

Claim:
In an agricultural sprayer having a frame adapted for forward movement over uneven terrain, a suspension system comprising: an upright strut shaft having a strut shaft axis and upper and lower ends; an axle having a strut journal mounting the upright strut shaft for axial movement along the strut shaft axis and for rotational movement therein; a wheel support connected to the lower end of the strut shaft; a steering arm connected for rotation generally about the strut shaft axis, wherein the strut shaft moves axially in the direction of the strut shaft axis with respect to the steering arm as the frame moves over the uneven terrain; an upper spring support; first and second upright spindles connecting the steering arm and the upper spring support; a spring supported between the upper end of the strut shaft and the upper spring support and providing cushioning for the wheel support as the strut shaft moves axially in the journal; and a spindle bracket fixed to the strut shaft and connected to the spindles for vertical movement with respect to the spindles as the strut shaft moves axially, the spindles and spindle bracket constraining the strut shaft for rotational movement with the steering arm for steering the wheel support while facilitating relative axial movement in the direction of the strut shaft axis between the upper end of the strut shaft and the steering arm.