| 摘要 |
Lift arms on a gang of implements support transport wheels which are movable from a raised field-working position to a lowered endwise towing position. Several of the wheels at the forward and aft ends of the towed gang of implements are fitted with castering pivots located adjacent the wheel hubs close to the wheel centerlines to lessen side loading and tire scuffing during turns. The castering wheels include a caster control assembly having at least four functions. First, a lock feature includes a spring-biased pin selectively engageable with the control assembly to secure the wheels in an in-line position to permit easy backing of the implements in the towing configuration. Second, a contact on the implement frame which engages the caster control assembly when the wheels are raised off the ground, cams the caster wheel to a preselected field-working position and prevents rocking of the wheel. Third, a bellevue washer on the caster control assembly limits shimmying of the wheel during transport. Fourth, the caster control assembly cooperates with a stop member on the lift arm to limit the angle through which the wheel can pivot. Combinations of caster wheel and non-caster wheel lift arm arrangements to reduce side loads and wheel scuffing while providing towing stability include two forwardmost caster wheels with all remaining wheels uncastered when three or four implements are towed endwise. When five or more implements are towed endwise, the first two wheels and the last wheel are castered, with an additional central caster wheel provided on a six-unit arrangement.
|
