Agricultural baler with improved needle coupling device

A baler comprising:

• a bale chamber;
• a plunger configured to compress crop material in the bale chamber in order to form a bale;
• a needle yoke comprising a plurality of needles configured to deliver twine through the bale chamber;
• a plurality of knotters configured to receive the twine from the plurality of needles;
• a bale length measurement and trigger device configured to measure a length of the bale in the bale chamber and to generate a trigger when a predetermined length is reached;
• a driving shaft located above the bale chamber and extending in a traverse direction of the baler;
• and
• a needle coupling device between the driving shaft and the needle yoke, the needle coupling device comprising:
• a crank arm attached to the driving shaft and co-rotating with the driving shaft;
• and
• a plurality of coupling members between the crank arm and the needle yoke, the plurality of coupling members configured for being brought from an uncoupled position in which the crank arm is not connected to the needle yoke to a coupled position in which the crank arm and the needle yoke are coupled when the bale length measurement and trigger device generates a trigger.

A baler comprising:

• a bale chamber;
• a plunger configured to compress crop material in the bale chamber in order to form a bale;
• a needle yoke comprising:
• a plurality of needles configured to deliver twine through the bale chamber;
• two needle support arms each having a first end and a second end, the second ends pivotally mounted around a fixed pivot axis extending in a transverse direction of the baler;
• and
• a needle carrying rod extending in the transverse direction of the baler and carrying the plurality of needles, the needle carrying rod mounted between the first ends of the needle support arms;
• a plurality of knotters configured to receive the twine from the plurality of needles;
• a bale length measurement and trigger device configured to measure a length of the bale in the bale chamber and to generate a trigger when a predetermined length is reached;
• a driving shaft located above the bale chamber and extending in a traverse direction of the baler;
• a needle coupling device positioned between the driving shaft and the needle yoke and the needle coupling device configured for establishing an uncoupling and a coupling between the driving shaft and the needle yoke, the needle coupling device configured for moving the needle yoke from a rest position to a twine delivery position and back, when the bale length measurement and trigger device generates a trigger;
• a driveable knotter shaft coupled to the plurality of knotters;
• and
• a knotter coupling device between the driving shaft and the driveable knotter shaft, the knotter coupling device configured to couple the driving shaft to the driveable knotter shaft based on a position of the needle yoke, the knotter coupling device comprising:
• a clutch between the driving shaft and the driveable knotter shaft;
• and
• a rod assembly comprising a rod connected to at least one of the two needle support arms of the needle yoke, the rod assembly configured for engaging the clutch such that the driving shaft is coupled to the driveable knotter shaft.