| 摘要 |
<p>A positioning apparatus (18) for boom structures (14, 16) is disclosed. The positioning apparatus (18) is comprised of a fixed frame assembly (24) mounted to vehicle (12), a slideable frame assembly (22) for vertical slideable movement with respect to fixed frame assembly (24), and a pivotable frame assembly (20) for rotatable movement with respect to slideable frame assembly (22). Boom structures (14, 16) are mounted on opposite sides of pivotable frame assembly (20). A system including hydraulic cylinders (86, 77, 96) moves boom structures (14, 16) between transit and operational configurations, vertically slides slideable frame assembly (22) and pivotably rotates pivotable frame assembly (20). The pivotal axis of the pivotable frame assembly (20) is above the center of gravity of the pivotable frame assembly (20) and attached boom structures (14, 16) to keep the boom structures (14, 16) pendulously stable when implement (10) strikes a bump in a field. Springs (112, 118) and shock absorbers (120) recenter pivotal frame assembly (20) relative to implement (10). Plates (36, 70) transmit between the vehicle (12) and the boom structures (14, 16) force components parallel to the pivotal axis so as to protect pin (76) from extraneous stress.</p> |
