Round bale forming apparatus

Abstract: A round baler is disclosed for forming crop material into cylindrical bales. The baler has a main frame (11), a pair of side walls (19), a crop pick-up (16) mounted on the main frame (11), and a tailgate (14) pivotally connected to the main frame (11). The tailgate (14) is operative between a closed position during which a bale is being formed in an expandable chamber, and an open position during which a formed bale is being discharged from the chamber. A sledge assembly (20), pivotally mounted on the main frame (11) for movement between a bale starting position and a full bale position, has crop engaging transverse rollers (21-23) for urging the crop material along a spiral path in the chamber for starting and forming a bale. An apron (32) is supported along a continuous path on the main frame (11) and tailgate (14) by a plurality of rotatable guide members (31, 33-36, 43-44). The path has an inner course (c) that cooperates with the rollers (21-23) on the sledge assembly (20) to define moveable walls of the chamber. A drive roll (38) moves the apron (32) along the continuous path. A take-up assembly, affixed to the sledge assembly (20), moves therewith between the bale starting position and full bale position to provide slack in the apron (32) under conditions where the tailgate (14) is moved from its closed position to its open position, thereby causing the drive roll (38) to become disengaged from the apron (32).

Description: 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 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 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. US-A-5,444,969 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 side walls, 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. The present invention relates to an improved round baler in which a cylindrical package of crop material is formed between expandable walls consisting of a combination of belts and rolls of the general nature described in the preceding paragraph. US-A-5,444,969 is an example of many prior art patents, assigned to New Holland North America, Inc., that disclose this type of round baler. This invention is directed to unique structural characteristics, described below which contribute to a round baler, featuring, among other things, enhanced performance, simplified construction and improved durability. Additionally, there is a noted improvement in the appearance of round bales formed by the baler of the present invention. According to the invention, there is provided a round baler for forming crop material into cylindrical bales, comprising: a main frame; a tailgate pivotally connected to said main frame and movable between a closed position for forming a bale in said baler and an open position for discharging a formed bale from said baler; a sledge assembly mounted on said main frame for movement between a bale starting position and a full bale position, said sledge assembly including conveying means having a crop engaging surface extending transversely of said main frame; an apron supported along a continuous path on said main frame and on said tailgate by a plurality of rotatable guide members, said apron path having an inner course that cooperates with said conveying means on said sledge assembly to define a bale forming chamber; a take-up assembly movable between a bale starting position and a full bale position for taking up the slack of said apron during bale formation; and a pick-up for feeding crop material into said chamber. This baler is characterized in that said take-up assembly includes take-up means affixed to said sledge assembly for movement therewith between said bale starting position and said full bale position. This mounting of the take-up means provides a simplified, yet effective design for a round baler with an expandable bale forming chamber including belts and transverse rolls. The resilient means of the take-up assembly now directly act on the sledge such that the movement thereof is controlled more effectively, especially during the first stage of the bale formation. The belt take-up assembly and sledge assembly then also operate in concert to improve belt tracking and to prevent surging of the cylindrical package of crop material during formation of the bale. In a baler having driving means which are operatively engageable with the apron, the take-up means can be mounted so as to cause automatic disengagement of the driving means under conditions where the tailgate is moved from the closed to the open position. Such configuration obviates the need to declutch the belt drive during bale discharge. This can be realized in a round baler having an expandable bale forming chamber defined in part by belts and rolls, wherein the belt take-up assembly is configured to yield slack in the belts during bale discharge to interrupt belt motion and avoid scuffing of the surface of the bale. Furthermore the belt take-up assembly can be configured to minimize contact between the bale and the belts during bale discharge. Advantageously the take-up means include a take-up arm carrying one or more rotatable guide members, such as take-up rolls, mounted on the distal end of the take-up arm for providing slack in the apron under conditions where the tailgate is moved from the closed position to the open position, thereby causing the drive means operatively engageable with the apron to become disengaged from the apron. A baler in accordance with the present invention will now be described in greater detail, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic side elevational view of a round baler in which the present invention is incorporated; the tailgate is in the closed position and the elements of the bale forming chamber are shown in their core starting condition; Figure 2, generally similar to Figure 1, is a diagrammatic side elevational view of a round baler 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; Figure 3, also generally similar to Figure 1, is a diagrammatic side elevational view of a round baler in which the tailgate is in the closed position and the elements of the bale forming chamber are shown in the full bale condition; and. Figure 4, also a diagrammatic side elevational view of a round baler, shows the tailgate in the open position and the relationship of the elements of the bale forming chamber after a bale has been discharged. The terms "front" and "rear" used throughout this description are defined with reference to the normal direction of travel of the baler during baling operations. However they are not to be construed as limiting terms. Figure 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. US-A-5,444,969 and US-A-4,870,812, both of which are hereby incorporated 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. 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 side walls 19' coplanar with side walls 19. A pick-up 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 Figure 1, through the partly full position shown in Figure 2, to the full bale position shown in Figure 3 and finally to the bale discharge position shown in Figure 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 fourth roll, a freely rotatable idler roll 31, also carried between arms 24. The bale forming chamber is further defined by an apron 32 comprising a plurality of laterally spaced side-by-side belts supported by guide rolls 33, 34, 35, rotatably mounted in tailgate 14, and roll 36, rotatably mounted on stationary arms 37, affixed to main frame 11. Apron 32 is also supported on a drive roll 38, mounted on main frame 11. Although apron 32 passes between roll 21 and idler roll 31, it is in engagement only with idler roll 31 and not with roll 21, which serves to strip crop material from the belts, in addition to its bale forming function. Suitable coupling means (not shown) connected to drive shaft 28 provide rotation of drive roll 38 causing movement of apron 32 along the varying paths in the directions indicated by the arrows in Figures 1, 2 and 3. An additional guide roll 40 in the main frame 11 ensures proper driving engagement between apron 32 and drive roll 38. A pair of take-up arms 41 (only one shown), integral with sledge assembly 20, are affixed to sledge arms 24 for movement between inner, intermediate, outer and bale discharge positions shown in Figures 1, 2, 3 and 4, respectively. Take-up arms 41, which carry additional guide rolls 43, 44 for supporting apron 32, are urged with sledge assembly 20 toward the innermost position (Figure 1), i.e., bale starting position, by spring 42, mounted between one of arms 41 and bracket assembly 39, secured to main frame 11. Spring 42, mounted outwardly from wall 19, is pivotally secured to arm 41 by journal means extending through access slot s in side wall 19. When the elements of round baler 10 are disposed as shown in Figure 1, an inner course c of apron 32 extends between guide roll 35 and idler roll 31 to form the rear wall of the core starting chamber while the inwardly facing peripheral surfaces of rolls 21, 22, 23 define in a general manner a rearwardly inclined cooperating front wall. Floor roll 18 defines the bottom of the chamber and with starter roller 30 provides an inlet for crop material. When round baler 10 travels across a field, pick-up tines 17 lift crop material from the ground and deliver it through the inlet. The crop material is carried rearwardly by floor roll 18 into engagement with apron inner course c (Figure 1) which urges it upwardly and forwardly into engagement with the rolls on sledge 20. In this manner crop material is coiled in a clockwise direction to start a bale core. Continued feeding of crop material into the bale forming chamber by pick-up tines 17 causes the apron inner course c to expand in length around a portion of the circumference of the cylindrical package of crop material as its diameter increases (Figure 2). Take-up arms 41 rotate with sledge assembly 20 about the coaxial horizontal axes of stub shafts 26 from their initial positions shown in Figure 1 toward their outer positions shown in Figure 3 to provide for expansion of the inner course of the apron in a manner similar to that of the prior art balers mentioned above, i.e., in effect the outer course of the belts of apron 32 is diminished in length while the inner course increases a like amount. After a cylindrical package of crop material has been formed in the fashion described and wrapped with twine or net in a well known manner to form a bale, tailgate 14 is opened and the bale is ejected rearwardly as shown in Figure 4. Subsequent closing of tailgate 14 returns the inner and outer courses of the belts of apron 32 to the locations shown in Figure 1. During bale formation, sledge assembly 20, due to its unification with the take-up assembly, also moves between a bale starting position (Figure 1) to a full bale position (Figure 3). This movement of sledge assembly 20 causes idler roll 31 to move along a generally arcuate path while maintaining apron 32 in close proximity to roll 21, thereby allowing roll 21 to strip crop material from the belts and prevent or reduce significantly the loss of crop material through the space between roll 21 and apron 32 during formation of a bale. Sledge assembly 20 is pushed outwardly towards its full bale position during bale formation as the crop material expands against rolls 21, 22, 23 and then subsequently is returned inwardly by apron 32 to the position shown in Figure 1. With the above description and general operation of baler 10 as a background, attention will now be directed to important features of this new take-up/sledge structure. As will become apparent, baler 10 is merely illustrative of one of the many round baler configurations to which the features of the present invention are adaptable. For example, varying the number of rolls on the sledge assembly would have no effect on the general aspects of the present invention. To further enhance understanding of the various features of the present invention, it should be noted that by unifying the sledge and take-up assemblies, many advantages are realized, not the least of which is the capability of interrupting the drive to the apron 32 during discharge. This obviates scuffing of the outer surface of the completed bale, without the need for mechanically declutching the belt drive mechanism. This is accomplished during movement of take-up arm 41, affixed to sledge assembly 20, between the bale starting position and the full bale position. Take-up rollers 43, 44 mounted on the distal end of the take arm 41, provide slack in the apron under conditions where the tailgate is moved from the closed position toward the open position causing the drive roll 38, normally operatively engageable with the apron 32, to become disengaged from the apron during discharge. The slack occurs under conditions where the belt path is reduced as the tailgate 14 begins to open and the take-up rolls 43, 44 are held in place by the sledge/take-up assembly, which does not move as the tailgate opens. Thus, the normal function of the take-up system is prevented until the bale is discharged. This avoids scuffing of the outer surface of the completed bale because the tendency for the belts to be driven in a direction contrary to the direction of the outer surface of the bale, rotating in a clockwise direction during discharge, is obviated. Another significant advantage is the reduction of belt idler roll damage caused by bale surging when the shape of the bale is not symmetrical. The take-up arm 41 prevents surging by holding the crop package forward against the sledge, i.e., it does not operate independent of the sledge. In prior art roll/belt balers, under uneven bale shape conditions the independent operation of the take-up assembly resulted in a tendency for it to have a deleterious influence on the proclivity of an unevenly shaped bale to surge rearwardly. Further, the take-up arm 41 of the present invention holds the bale at a higher location during bale ejection, resulting in less interference during bale discharge. It should also be noted that this unique sledge and take-up arrangement is less costly and less complex than the arrangement used in prior art round balers in that there is a common pivot axis for the sledge and the take-up systems. Additionally, this enhances belt tracking by reducing the tendency for the rolls of unified structure to become askew. While the preferred structure in which the principles of the present invention have been incorporated is shown and described above, it is to be understood that the invention is not to be limited to the particular details, as shown and described above, but that, in fact, widely different means may be employed in the practice of the broader aspects of the invention. For example, the set of rolls 21-23 of the sledge assembly 20 may be replaced by other conveying means such as parallel conveyor belts or a chains-and-slats apron.

Claims: A round baler for forming crop material into cylindrical bales, comprising: a main frame (11); a tailgate (14) pivotally connected to said main frame (11) and movable between a closed position for forming a bale in said baler (10) and an open position for discharging a formed bale from said baler; a sledge assembly (20) mounted on said main frame (11) for movement between a bale starting position and a full bale position, said sledge assembly (20) including conveying means (21-23) having a crop engaging surface extending transversely of said main frame (11); an apron (32) supported along a continuous path on said main frame (11) and on said tailgate (14) by a plurality of rotatable guide members (31, 33-36), said apron path having an inner course (c) that cooperates with said conveying means on said sledge assembly (20) to define a bale forming chamber; a take-up assembly (41-44) movable between a bale starting position and a full bale position for taking up the slack of said apron (32) during bale formation; and a pick-up (16) for feeding crop material into said chamber; characterized in that : said take-up assembly (41-44) includes take-up means (41, 43, 44) affixed to said sledge assembly (20) for movement therewith between said bale starting position and said full bale position. A round baler according to claim 1, characterized in that : it further comprises drive means (28, 38) for moving said apron (32) along said continuous path, said drive means (28, 38) including means (38) operatively engageable with said apron (32); and said affixed take-up means (41, 43, 44) are mounted to said sledge assembly (20) as to cause said means (38) operatively engageable with said apron (32) to become disengaged from said apron (32) under conditions where said tailgate (14) is moved from said closed position to said open position. A round baler according to claim 2, characterized in that : said means operatively engageable with said apron (32) comprise a drive roll (38) having an outer generally cylindrical surface in frictional engagement with said apron (32) under conditions where said tailgate (14) is closed; and said affixed take-up means (41, 43, 44) include at least one rotatable take-up roll (43/44), engaging said apron (32) and providing slack in said apron (32) under conditions where said tailgate (14) is moved from said closed position to said open position, thereby causing said drive roll (38) to become disengaged from said apron (32). A round baler (10) according to claim 3, characterized in that : said affixed take-up means (41, 43, 44) comprise a pair of take-up arms (41) affixed to said sledge assembly (20) for movement therewith; and said at least one take-up roll (43/44) is mounted between the distal ends of said take-up arms (41). A round baler according to claim 4, characterized in that said affixed take-up means (41, 43, 44) comprise a second take-up roll (44) mounted adjacent said take-up roll (43) between the distal ends of said take-up arms (41), said take-up roll (43) and said second take-up roll (44) acting in concert to provide slack in said apron (32) under conditions where said tailgate (14) is moved from said closed position to said open position. A round baler according to any of the preceding claims, characterized in that said apron (32) comprises a plurality of side-by-side belts. A round baler according to any of the preceding claims, characterized in that said sledge assembly conveying means comprise at least two driven rolls (21-23), the peripheral surfaces of which engage said crop material under conditions where said pick-up (16) feeds crop material into said chamber, said rolls (21-23) driven in a direction that urges said crop material along a spiral path is said chamber. A round baler according to claim 7, characterized in that one of said at least two driven rolls (21-23) is pivotally mounted on said main frame (11). A round baler according to any of the preceding claims, characterized in that said take-up assembly (41-44) further includes a spring assembly including resilient means (42) for providing a force to urge said affixed take-up means (41, 43, 44) and said sledge assembly (20) to said bale starting position. A round baler according to claim 9, when appended to claim 4, characterized in that said resilient means (42) is affixed at one end to at least one of said take-up arms (41) and affixed at the other end to said main frame (11), whereby said force urges said affixed take-up means (41, 43, 44) and said sledge assembly (20) to pivot about said at least one of said two driven rolls (23).

Inventors: UNDERHILL KENNETH R, UNDERHILL, KENNETH R.
Applicants: CNH BELGIUM NV, CNH BELGIUM N.V.
Application year: 1999
Main classification: A01F15
IPC codes: A01F15