Rigid cutterbar over travel

A cutter bar assembly for an agricultural vehicle header, comprising:

• a header frame;
• an infeed frame extending from the header frame in a forward direction, the infeed frame joined to the header frame at an end proximal to the header frame by a pivot;
• a cutter bar attached to a respective distal end of the infeed frame;
• a stop link joined by a pivot to the infeed frame and by a pin slot joint to the header frame, wherein the pin slot joint comprises a slot in the stop link and a pin fixed to the header frame at a point below the pivot joining the infeed frame to the header frame;
• and
• a hydraulic actuator joined at one end to the header frame by a pivot and at an opposite end to the support arm by a sliding joint comprising a pin slot joint comprising a pin fixed to the actuator and a slot fixed to the infeed frame, wherein:
• the actuator can lift and hold the infeed frame in a raised position in a rigid mode;
• the sliding joint joining the hydraulic actuator to the infeed frame and the stop link enable the infeed frame to move upward from the raised position in the rigid mode when the infeed frame is subjected to a lifting force at its distal end;
• the cutter bar assembly further comprises an actuator link joined by sliding joints to the header frame and infeed frame in parallel with the hydraulic actuator to limit travel of the hydraulic actuator, wherein the sliding joints joining the actuator link to the header frame and infeed frame comprise a slot in the actuator link and a pin fixed respectively to each of the header frame and the infeed frame;
• and
• the cutter bar assembly further comprises a position sensor for detecting when the infeed frame is moved upward from the raised position in the rigid mode by a lifting force at its distal end.