| 摘要 |
<p>A tractor having a steerable axle (15) that pivotally moves laterally in response to a corresponding steering action of the steerable wheels (17) mounted on the steerable axle (15) and is also pivotally supported for oscillatory pitching movement about a longitudinal axis is disclosed wherein an oscillation stop is provided in the form of an arcuate track (24) mounted to the steerable axle (15) and a pair of transversely spaced rollers (26a,26b) engageable with the arcuate track (24) through the entire range of lateral movement of the axle (15) to limit the amount of permissible oscillatory pitching movement. The arcuate track (24) has a center of curvature that coincides with the vertical pivot axis (12) for the lateral movement of the axle (15). The rollers (26a,26b) are spaced on opposing sides of the longitudinal axis and have rotational axes that are generally aligned with the center of curvature of the arcuate track (24). The upper surface of the arcuate track may have an undulating configuration to vary the permissible vertical pitching motion of the axle as the steering angle of the steering mechanism changes. <IMAGE></p> |
