MACHINE FOR FORMING CYLINDRICAL BALES OF CROP

Abstract: A baling machine has belts (42) which define a chamber (50) in which a bale (76) is formed. The belts are trained over rolls (20 etc.) including belt take-up rolls (36, 38, 40) mounted on a pivotted arm (58) moved by a piston and cy­ linder unit (66) which is connected at its other end to a gate (34) of the machine. In order to have the choice of producing a bale with a soft core the arm (58) has a plurality of connection points (68, 70) one (70) of which is close to the arm pivot (56) and a geometric line through the axis (71) of the unit will pass near the arm pivot so that tension applied by the unit to the belts (42) during formation of the bale core is insig­ nificant. The angle between the axis (71) of the unit (66) and a line (not shown) joining the connection point (67) of the unit to the gate (34) and the arm pivot (56) is 0° to 7°, and desirably 3° to 4°.

Description: This invention relates to a baling machine for forming cy­ lindrical bales of crop having a frame, a belt or belts defining a baling chamber, an arm pivotted on the frame, a belt take-up roll which is mounted on the arm and over which the belt or belts are trained, a gate for the formed bales, a piston and cylinder unit connected pivotally at one end to the gate and connectible pivotally at the other end to the arm. Machines, towed by a tractor, for forming large cylindri­ cal bales of hay (so called "round balers") are well known. As the machine advances, the crop is removed from a windrow by a pick-up mechanism and delivered rearwardly to a baling chamber where it is rolled into a bale between oppositely moving belt runs, the growing bale rotating about a hori­ zontal axis and the baling chamber expanding with the bale. The belts are trained over rolls which extend laterally of the machine. Some of these rolls are mounted on a pivotted arm at either side of the machine which swings and thereby accommodates the increasing size of the bale by reducing the take-up of the belts. In one type of round baler currently marketed, in order to produce a dense bale the arm is loaded against its swinging movement by a piston and cylinder unit which is also con­ nected to the gate for loading it against opening during baling and for opening it on completion of a bale. A uni­ formly dense bale is normally required However, in some conditions of harvesting the hay cannot be dried sufficiently before baling, and then it is desi­ rable to produce a bale which has a "soft" core and a high density outer shell. To achieve this the hydraulic pres­ sure in the piston and cylinder unit could be reduced to lessen the load on the pivotted take-up roll arm, but the unit would then not perform its second function of preven­ ting opening of the gate during baling. The baling machine of the present invention can be used to make either a bale of uniform density or a bale with a soft core and dense outer shell by means of an arrangement which is simple and is easy to work. According to the present invention the arm has a plurality of positions to which the said other end is selectively pi­ votally connectible, a said position being such that, when the unit is connected to it, a geometric line along the longitudinal axis of the unit is sufficiently close to the pivot of the arm that the tension applied to the belt or belts by the unit during formation of the bale core is in­ significant. A said position can be such that, when the unit is connec­ ted to it, at start-up of baling the longitudinal axis of the unit is at an angle of 0° to 7° to a geometric line joining the said pivot connections of the unit to the gate and of the arm to the frame Preferably the range is 2° to 4°, particularly 3° to 4°. An embodiment of the invention will now be described with reference to the accompanying diagrammatic drawings in which: Fig. 1 shows the right hand side (considered when facing in the direction of travel) of a ma­ chine for forming large cylindrical bales of hay, in its condition before baling has started; Fig. 2 shows the machine of Fig. 1 at the stage of completion of baling when a bale is at its maximum size; and Fig. 3 shows the machine of Fig. 1 with its gate fully open after bale discharge. In the drawings, the machine includes a main frame 10 moun­ ted on a pair of wheels of which only the right hand wheel 12 is shown. The main frame has an upright fore-and-aft extending wall 14 on either side connected by transverse beams (not shown). A draft tongue 16 is connected to a transverse beam at the front of the frame 10 and extends forwardly for attaching the baler to a tractor (also not shown) which draws the machine. A plurality of lateral rolls extends over the width of the machine. One set of rolls 18, 20, 22, 24, 26 is journalled in the side walls 14, whilst another set consisting of rolls 28, 30, 32 is journalled in a swingable gate 34. There is also a pair of chamber restricting rolls 36, 38 and two belt take-up rolls 40, 41. Six rubber belts 42 are trained side-by-side over the rolls, with the exception of the roll 18 which acts as a stripper roll, to provide the configuration shown and they move in the direction indicated by arrows 44, the stripper roll 18 being driven anti-clockwise as viewed in the figures. How­ ever, alternate belts only are trained over the lower fore­ most roll 22, whilst the remaining belts by-pass this roll, to provide a staggered array which is of no significance in relation to the present invention but which is described in our co-pending European patent application 82106409. Up­ wardly extending runs 46, 48 of the belts 42 define a bale-­ forming chamber 50 the ends of which are provided by the side walls 14 and gate 34 and which has an inlet 52 for crop received from a pick-up 54 beneath it. In order to accommodate the increasing diameter of a growing bale core in the bale-forming chamber 50, the size of the chamber must also increase and a belt take-up and tensio­ ning mechanism is provided at either side of the machine. These mechanisms include: a pair of rearwardly extending idler arms which are mounted rigidly at the forward end of the main frame 10 on a horizontal transverse shaft 56, pro­ viding a pivot connection for the arms, and of which the right hand arm 58 only is shown; the belt take-up roll 40 which is supported at either end at an intermediate loca­ tion on the arms 58; and the pair of chamber restricting rolls 36, 38 supported at the free ends of the arms. The arms are biased in an anti-clockwise direction by a pair of springs, one on either side of the main frame 10, of which only the right hand spring 60 is shown and only its arrangement will be described, the other being similar. The spring 60 is connected at its lower end by a post 62 to a lever portion 64 of the arm 58, the portion 64 being rigid with the pivot shaft 56, and at its upper end to one arm of a bell crank 66 the other arm of which bears one end of the take-up roll 41. The lever portion 64 is also pivotally connected to the cylinder of a piston and cylin­ der unit 66 of which the piston is in turn pivotally con­ nected to the gate 34 at a point 67, a similar arrangement being provided also on the left hand side of the machine. The piston and cylinder unit 66 has two functions the first of which is in relation to the idler arm 58 and bale forma­ tion, and the second of which is to open and close the gate 34 and to maintain it closed. The lever portion 64 has at its free end a piston and cylinder unit connection point 68, at the same horizontal level as the point 67, for use when baling in normal conditions. However, a further con­ nection point 70, located very close to the pivot shaft 56, is also provided on the lever portion 64 and is to be se­ lected when the machine is used for baling hay which is not sufficiently dry. This latter connection point 70 lies, of course, on the longitudinal axis 71 of the unit 66, and this is at an angle of 9° to the horizontal before baling starts as shown in Fig. 1. The longitudinal axis 71 is more importantly also at an angle of 3° to a geometric line joi­ ning the pivot connections 67 and 56, but for reason of clarity difficulties this is not illustrated in the dra­ wings. Thus a geometric line along the longitudinal axis 71 of the unit 66 is sufficiently close to the pivot of the idler arm 58 that the moment of the unit about the arm is substantially zero or close to zero. The significance of this will be explained when the baling operation is de­ scribed later below. In addition to being connected to the piston and cylinder unit 66, the lever portion 64 is also pivotally attached at its inward face to a subsidiary piston and cylinder unit 72 which serves to bring about displacement of the idler arm 58 if it is desired to open the gate 34 when the baling chamber 50 is empty. The subsidiary unit 72 is con­ nected to the free end of the lever portion 64 at the same point 68 as can be used, as mentioned above, simultaneous­ ly for the piston and cylinder unit 66. An idler arm spring-loaded stop 74 is attached to either side wall 14 at an upper portion thereof at a position cor­ responding to the maximum swing of the arm 58 and related to the maximum size of a bale 76. A switch 78, electrical­ ly connected to an indicator for the operator, can be pro­ vided just above the stop 74 to be triggered by it when the maximum swing is reached. Alternatively a gate switch 80 which is shown only in Fig. 2 can be disposed between the gate 34 and the wall 14. This switch 80 similarly is electrically connected to an indicator, and the switch 80 will be triggered when the gate 34 begins slightly to be forced open. The indicators are not shown. Furthermore, three fixed-position rolls 82 which are il­ lustrated only in Fig. 2 are disposed around the maximum circumference of the bale 76 so as to support the belts 42 in order to keep the bale cylindrical. In operation, hay lying in a windrow is lifted and conveyed to the baling chamber 50 where the oppositely moving runs 46, 48 of the belts 42 cause the crop to turn clockwise (as viewed in the Figures) so as to form a bale core of increasing size which eventually overcomes the tension in the belts brought about by the belt take-up and tensioning mechanisms, and the idler arms 58 consequently swing up­ wardly and thus the chamber 50 increases in size. In wet conditions a bale with a soft core, but still with a dense outer shell, may be required and the piston and cylinder unit 66 is then attached as already described to the connection point 70 on the lever portion 64. The ef­ fect of this is that the tension applied to the belts 42 by the unit 66 during formation of the growing bale, i.e. the bale core, is insignificant and hence the core will be soft. The density of the bale remains low until the idler arms 58 abut the spring loaded stops 74 when the baler starts to operate as a machine with a fixed-size chamber and therefore the density of the outer layers increases at this stage of bale formation. Finally the spring loa­ ding of the stops 74 will be overcome and they will move against, and trigger, the switches 78 indicating to the operator the completion of the formation of the bale 76. The tying of the bale 76 and its ejection through the gate 34 are conventional and therefore will not be described. In normal harvesting conditions the piston and cylinder unit 66 will be attached to the connection point 68 on the lever portion 64 so that the belts 42 will be under ten­ sion during formation of the core which will then be dense rather than soft. The baling machine is thus well adapted to producing as needed either a bale which is dense throughout or a bale which has a soft core and dense outer layers. At the same time, even when a soft core bale is being produced, the piston and cylinder units 66 will be capable of maintai­ ning the gate 34 in its closed condition and will be able to open and close the gate on completion of a bale.

Claims: 1. A baling machine for forming cylindrical bales of crop having a frame (10), a belt or belts (42) defining a baling chamber (50), an arm (58) pivotted on the frame (10), a belt take-up roll (40) which is mounted on the arm (58) and over which the belt or belts (42) are trained, a gate (34) for the formed bales, a piston and cylinder unit (66) connected pivotally at one end to the gate (34) and connectible pivotally at the other end to the arm (58), characterised in that the arm (58) has a plurality of positions (68, 70) to which the said other end is selectively pivotally connectible, a said position (70) being such that, when the unit (66) is connected to it, a geometric line along the longitu­ dinal axis (71) of the unit (66) is sufficiently close to the pivot of the arm (58) that the tension applied to the belt or belts (42) by the unit (66) during for­ mation of the bale core is insignificant. 2. A baling machine according to claim 1 characterised in that a said position (70) is such that, when the unit (66) is connected to it, at start-up of baling the lon­ gitudinal axis (71) of the unit (66) is at an angle of 0° to 7° to a geometric line joining the said pivot connections of the unit (66) to the gate (34) and of the arm (58) to the frame (10). 3. A baling machine according to claim 2 characterised in that the angle is 2° to 4°. 4. A baling machine according to claim 3 characterised in that the angle is 3° to 4°. 5. A baling machine according to any preceding claim cha­ racterised in that it includes a spring loaded abut­ ment (74) disposed to be contacted by the arm (58) to increase belt tension during completion of the bale. 6. A baling machine according to claim 5 characterised in that it includes a switch (78) and an indicator connec­ ted thereto, the abutment (74) being movable against the switch (78) and the switch (78) being caused there­ by to trigger the indicator showing completion of a bale. 7. A baling machine according to any of claims 1 to 5 cha­ racterised in that it includes a switch (80) and an indicator connected thereto, the switch (80) being ar­ ranged between the gate (34) and frame (10) to trigger the indicator showing completion of a bale on the gate (34) starting to open. 8. A baling machine according to any preceding claim cha­ racterised in that it includes a subsidiary piston and cylinder unit (72) connected between the frame (10) and arm (58) so as to be capable of opening the gate (34) when the baling chamber (50) is empty. 9. A baling machine according to any preceding claim cha­ racterised in that it includes a plurality of fixed-­ position rolls (82) disposed to act as abutments for the belt or belts (42) at the maximum circumference of a bale. 10. A baling machine according to any preceding claim cha­ racterised in that the said arm (58) has a lever por­ tion (64) and the said plurality of positions (68, 70) is on the lever portion.

Inventors: VIAUD, JEAN
Applicants: DEERE & COMPANY
Application year: 1986
Main classification: A01F15
IPC codes: A01F15