Patent ID: 8141480

Claim:
In a round baler having a wheel-supported main frame having a front end and an opposing rear end and adapted for movement in a direction of travel through a field of cut crop material, a bale-forming chamber supported on said main frame and including a plurality of belts and rollers arranged to form a cylindrical bale by rotation of crop material within the bale-forming chamber, a pickup mounted to the forward end of said main frame and adapted to pick up crop material from the field and feed it into the bale-forming chamber, a tailgate pivotably affixed to the bale-forming chamber and adapted to pivot vertically between a closed position where a bale is captured in the bale-forming chamber and an open position where the bale can be ejected, and a wrapping material dispensing mechanism affixed to the main frame and located peripheral to the bale-forming chamber and onto the cylindrical surface of the formed bale in the chamber, the improvement comprising: an array of first sensors supported on said baler and located in a position to sense the reflectance of the cylindrical surface of the formed bale in the bale-forming chamber and initiate a first output signal; a second sensor supported on said baler and located in a position to measure a quantity of wrapping material dispensed from the dispensing mechanism and to initiate a second output signal representative thereof; a bale size indicator; and a controller configured to receive said first output signal and said second output signal, determine the length of wrapping material dispensed from the dispenser from initiation of bale wrapping dispensing until said array of first sensors sense a change in reflectance caused by the presence of said wrapping material on said cylindrical surface of the bale, determining a measured bale size using said length, and calibrating said bale size indicator using said measured bale size.