| 主权项 |
1. A foldable marker mounted on a wing section of an agricultural implement, the foldable marker comprising:
an elongate inboard arm, the inboard arm defining a longitudinal axis along its length and a transverse axis that is orthogonal to the longitudinal axis, the inboard arm having an inner tab fixed near one end of the inboard arm and at least one stop fixed near an opposite end of the inboard arm; an outboard arm, the outboard arm having a slotted plate with an elongated slot formed in the slotted plate; a linkage assembly connecting the inboard and outboard arms to form an outer pivot joint so that the marker can be shifted between a folded and an unfolded arm condition, the linkage assembly comprising at least one base link having an upper end and a lower end, the lower end being pivotally attached to the inboard arm, and at least one sliding link having an inboard end and outboard end, the inboard end of the sliding link being pivotally attached with the upper end of the base link, and the outboard end of the sliding link being slidably mounted with the slot of the slotted plate such that movement of the outboard end of sliding link with respect to the outboard arm is constrained to movement along the slot; a support frame mounted at an outboard end of the wing section, the support frame including a lower stop, a pair of upper tabs, and a support bracket, the support bracket attached to the inboard arm to form an inner pivot joint, wherein the support frame is attached to the wing section so that the longitudinal axis is substantially parallel to a longitudinal axis of the wing section when the marker is unfolded and the longitudinal axis is substantially coaxially aligned with a longitudinal axis of the wing section along the fore-and-aft direction of the implement when the marker is unfolded; a hydraulic cylinder assembly comprising a movable piston to drive the arms between the folded and unfolded arm conditions, wherein one end of the cylinder assembly is attached to the upper tabs of the support frame and an opposite end is attached to the upper end of the base link and the inboard end of the sliding link such that the base link and sliding link move with the piston, wherein the marker is shiftable from the unfolded arm condition to the folded arm condition by shifting the cylinder assembly from an extended position to a retracted position such that piston retraction causes the sliding link to slide in the slot of the slotted plate until the sliding link reaches an upper end of the slot and further piston retraction causes pivoting of the outboard arm relative to the inboard arm until the base link engages the stop on the inboard arm, and piston retraction also causes pivoting of the inboard arm relative to the support frame until the inboard arm is in an upright position, and the foldable marker is shiftable from the folded arm condition to the unfolded arm condition by shifting the cylinder assembly from the retracted position to the extended position such that the arms pivot downwardly relative to the support frame and the inboard arm pivots downwardly until the inboard arm is generally horizontal and the tab engages the lower stop to restrict further downward movement of the inboard arm; and a coulter disc supported by the arms and constructed so that the coulter disc engages the ground leaving a visible demarcation in the field as the marker is moved as part of the implement when in the unfolded arm condition. |
