| 摘要 |
SPRAY BOOM HEIGHT ADJUSTMENT A spray boom assembly has an elongate boom carrier supported on walking axles near its opposite ends. Each of the walking axles consists of a pair of parallelogram linkages extending respectively to the front and back of the boom carrier. The parallelogram linkages are linked by an hydraulic cylinder or actuator that can be extended to rotate the parallelogram linkages downwards about their pivotal connections to the boom carrier. This raises the boom carrier without changing its orientation. Thus, the boom spray pipe can be connected directly to the boom carrier to be raised and lowered with it. No adjustment of the nozzle orientation is necessary when the boom height is changed. Another parallelogram linkage arrangement is used to connect the centre of the boom carrier to a towing vehicle. In preferred embodiments, the boom is made in two parts that are pivotally connected to a common central boom carrier support. The boom can then be shifted from a field spraying position to a transport position simply by unlatching the boom parts from their spraying positions and driving the towing vehicle forwards. The walking axles are pivotally mounted on the boom carrier for pivotal movement around vertical axis. This movement is controlled by hydraulic cylinder so that in the transport position, the walking axles are generally in line with the respective boom sections. |
