Abstract: A round baler having a shiftable repositioning member for moving a completed, discharged bale of hay away from the baler is provided with an interlock mechanism for preventing movement of the repositioning member until such time that the bale has been discharged from the chamber. A sensor is located on a side of the baling chamber to determine the absence of a bale, and preferably takes the form of a rounded element biased toward a position normally protruding into the chamber. The presence of a bale within the chamber causes the element to shift outwardly and thereby close a valve interposed in a hydraulic circuit for providing motive fluid power to a piston and cylinder assembly that, in turn, drives the repositioning member.

Abstract: During the process of binding a bale of crop material with binding twine in a crop baler, malfunction of the knotter is checked once upon completion of the binding sequence for one bale, and then a second time after the twine has been prepared by the knotter for formation of the next bale. The monitoring system is particularly appropriate for a double knotting mechanism in which each knotter operates through two complete operating cycles during each actuation thereof, a first cycle to complete a knot associated with the just finished bale, and a second cycle to complete a knot in two separate strands of twine to prepare the same for the next successive bale.