Round bale forming apparatus

#The present invention relates to agricultural apparatus for forming and wrapping cylindrical packages of crop material, generally referred to as round balers, and more particularly to a round baler in which a package of crop material, formed in an expandable, generally cylindrically shaped forming chamber, is wrapped with twine, plastic or net to produce a round bale, and then discharged from the baler.

#Round balers generally have a bale forming chamber defined by a pair of opposing side walls associated with an array of side-by-side belts, transverse slats trained on chains, a plurality of transverse rolls or a combination of these various elements, e.g., rolls and belts. During field operation, windrowed crop material such as hay is picked up from the ground and fed into a fixed or variable diameter bale forming chamber. The hay is then rolled into a cylindrical package, wrapped with twine, net or the like and ejected onto the ground for subsequent handling.

#U.S. Pat. No. 5,444,969, issued Aug. 29, 1995 in the name of Robert A. Wagstaff, et al, discloses a prior art round baler of the general nature described above. In this particular type of baler an expandable chamber is defined by a pair of sidewalls, and a plurality of side-by-side belts cooperating with a plurality of transverse rolls, mounted between a pair of pivotally mounted arms. The chamber includes an inlet opening in the front through which crop material is fed. The aforementioned arrangement of rolls and arms is commonly referred to as a sledge assembly. Also shown in the disclosed baler is a pair of take up arms pivotally mounted on the main frame, between which arms a pair of guide rolls are journalled. The outer surfaces of the guide rolls are urged against the belts to maintain belt tension and thereby prevent slack from occurring in the belts during expansion and contraction of the chamber.

#FIG. 1 is a diagrammatic side elevational view of a round baler incorporating the invention to which the aforementioned parent patent application is directed. The tailgate of the baler is in the closed position and the elements of the bale forming chamber are shown in their core starting condition.

#FIG. 2, generally similar to FIG. 1, is a diagrammatic side elevational view of the round baler of FIG. 1 in which the tailgate is in the closed position and the elements of the bale forming chamber are shown in an intermediate bale forming condition.

#FIG. 3, also generally similar to FIG. 1, is a diagrammatic side elevational view of the round baler of FIG. 1 in which the tailgate is in the closed position and the elements of the bale forming chamber are shown in the full bale condition.

#Referring to the drawings for a detailed description of the preferred embodiment of the invention, FIG. 1 shows the cross section of a round baler 10 of the type having an expandable chamber defined in part by belts and rolls. This type of expandable chamber is disclosed in various prior art patents, e.g., U.S. Pat. No. 5,444,969 mentioned above, and earlier U.S. Pat. No. 4,870,812, issued Oct. 12, 1989 in the name of Richard E. Jennings, et al, both of which are hereby incorporated is by reference. It should be noted that throughout this description the drawings are diagrammatic in nature to best show the elements of the invention. To this end, in many instances only one element in a pair is shown, especially in those cases where identical elements exist, disposed on opposing sides of the baler, e.g., wheels. It should also be noted that baler 10 shown in FIGS. 1-4 is the preferred embodiment to which the above mentioned parent application is directed, which baler, now to be described in detail, has been provided with improvements to which the present application is directed. At the heart of this application are these improvements which will also be described below, subsequent to the detailed description of baler 10.

#To this end, baler 10 has a main frame 11, comprising a plurality of rigid interconnected structural elements including a pair of side walls 19 (only one shown). Main frame 11 is supported by a pair of wheels 12 (also only one shown). A forwardly mounted tongue 13, integral with main frame 11, provides for connection to a tractor. Pivotally connected to side walls 19 by a pair of stub shafts 15 (only one shown) is a tailgate 14 which is closed during bale formation. Tailgate 14 includes sidewalls 19' coplanar with side walls 19. A pickup 16, mounted on main frame 11, includes a plurality of tines 17, the tips of which are movable along a predetermined path to lift crop material from the ground and deliver it rearwardly toward a floor roll 18, rotatably mounted on main frame 11.

#An expandable chamber for forming bales is defined partly by a sledge assembly 20 comprising a plurality of transversely extending rolls 21, 22, 23 journalled at their ends in a pair of spaced apart arms 24, one of which is shown. These arms are pivotally mounted on stub shafts 26 for providing movement of sledge assembly 20 from the bale starting position shown in FIG. 1 through the partly full position shown in FIG. 2 to the full bale position shown in FIG. 3, and finally to the bale discharge position shown in FIG. 4. Rolls 21, 22, 23 are driven in a counter-clockwise direction by conventional means (for example, chains and sprockets) coupled via an appropriate drive train to a drive shaft 28. A starter roll 30, located adjacent roll 23, is also driven counter-clockwise. Sledge assembly 20 includes a forth roll, a freely rotatable idler roll 31, also carried between arms 24.