Planter coulter apparatus with mechanical overload protection

An apparatus for use with a planter assembly constructed to move in a transport direction where the planter assembly includes support wheels mounted to the underside of a carrier frame, the apparatus comprising:

• a bar pivotally mounted to the underside of the carrier frame for pivotal movement between a transport position and a functional position;
• an arm member having an arm length dimension and forming a bearing surface, the arm member pivotally linked to the bar at the first end via a first pivot pin;
• a hydraulic cylinder pivotally linked at a first end via a second pivot pin to the second end of the arm member, the second end of the cylinder pivotally linked to the carrier frame, the cylinder for driving the bar between the transport and functional positions;
• and
• an overload locking member securable to the bar such that the bearing surface bears there against placing a secondary force thereon when a draft force is applied to the bar wherein, the locking member fails when the secondary force exceeds a threshold force.