| 摘要 |
An agricultural implement has a first frame portion for coupling to a tractor and a second frame portion has one end pivotally connected to the first frame portion. The pivotal connection is such that the second frame portion will pivot with respect to the first frame portion only when a force exerted on the second frame portion exceeds a pre-determined magnitude. A carrier, upon which are mounted working tools, is pivotally connected to the other end of the second frame portion and there is a spring device between the carrier and the second frame portion. This spring device exerts such a force that the outer end portion of the carrier can only pivot in the direction of normal operation of the implement.
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