GB2045156A

GB2045156A - Crop roll forming machines and drive systems therefor

Info

Publication number: GB2045156A
Application number: GB8010200A
Authority: GB
Original assignee: Sperry Corp
Current assignee: Sperry Corp
Priority date: 1979-03-29
Filing date: 1980-03-26
Publication date: 1980-10-29
Also published as: CA1126079A; DE3011183C2; FR2457635B1; AU535349B2; DE3011183A1; BR8001892A; AU5693380A; GB2045156B; FR2457635A1

Abstract

A crop roll forming machine has a bale forming means in the form of an upper apron 46 which can be driven by drive means in a normal first direction of rotation or in a second direction of rotation Y opposite to the first direction. Control means mounted on a frame of the machine are movable between a first position and a second position for cooperative interaction with the drive means and the upper apron 46 to selectively cause the upper apron 46 to cease being driven in the first direction and cause it to be driven in the opposing second direction Y when the control means is moved from the first position to the second position. Reversal of the direction of movement of the upper apron 46 causes a completed crop roll R to be ejected rearwardly from the machine onto the ground. The said control means is actuated by raising the tailgate 20. <IMAGE>

Description

SPECIFICATION Crop roll forming machines and drive systems therefor This invention relates to crop roll forming machines (e.g. for forming large cylindrical bales of crop material, commonly called round bales) and to drive systems for such machines. More specifically, it is concerned with a machine which permits completed bales to be discharged from a roll forming region of the machine onto the ground by the automatic reversing of a bale forming means or upper apron of the machine.

Hitherto, it has been the custom to harvest forage crops by mowing the particular crop, letting it dry in the field, forming the dried crop material into windrows and passing a hay-baling machine over and along these windrows to form the crop material into rectangular bales. Recent practice has shown that the formation of crop material into large compact rolls, rather than rectangular bales as formerly done, permits the crop material to be deposited in roll form and left in fields for extended periods of time. The ability to leave these rolled bales in fields obviates the additional steps required in the traditional rectangular baling process of gathering the bales and transporting them to a storage area protected from the elements. This new technique of forming large round bales has created a baling system that can be operated by one person.This is in marked contrast to the traditional practice of forming rectangular bales where the labour of several people was required to effect the cutting, drying, windrowing, baling, gathering and storing of the crop material.

Several methods of forming compact cylindrical rolls of crop material have evolved through the years. The most successful of these methods involves the forming of crop rolls by picking up a swath or windrow of crop material from the field and directing it onto a lower conveyor. This conveyor transports the material to a roll or bale forming region where an upper apron or flight of belts, usually positioned above and adjacent the conveyor, moves in a suitable direction to rotate the crop material with which it is brought into contact. The increasing popularity of these crop roll forming machines has seen their use broaden from rolling wintering forage for livestock to rolling high protein crops, such as alfalfa, for dairy livestock. Therefore, these machines are the focal point of many ideas for developing both labour-saving and time-saving apparatus.

Crop roll forming machines that produce large cylindrical crop rolls utilise some form of a tailgate which is pivotally mounted on the frame of the machine. The tailgate is elevated upon completion of the crop roll or when it is desired to discharge a less than full size bale for any of a variety of reasons from the roll forming region. The tailgate follows a predetermined arc of travel, generally pivoting about a fixed point on the frame.

Prior crop roll forming machines require the operator, who is located in the operator's area of a prime moving vehicle, such as a tractor which draws the machine, to perform a series of manual operations after completing the formation of the large crop roll and prior to recommencing the roll forming process or cycle.

Generally, these manual steps require the stopping of the roll forming machine and the towing tractor, the initiation of the wrapping of the completed crop roll, stopping the power take-off shaft from the tractor, opening the tailgate, restarting the power take-off shaft to power the components of the roll forming machine to assst in discharging the bale, closing the tailgate and finally restarting the forward motion of the tractor and the roll forming machine. One way to save time is to reduce the number of manual steps which the roll forming machine operator must take after the completion of the formation of each bale.

The current commercial crop roll forming machines generally discharge the completed crop material package from the roll forming region either by pivoting the tailgate rearwardly and upwardly, thereby permitting the bale to drop directy onto the ground, or by first elevating the tailgate and then activating the conveyor lower apron which forms the lower limit of the roll forming region. In the latter case, the lower apron is activated by the operator restarting the power take-off shaft, which peviously has been disengaged, thereby causing the bale to be urged rearwardly out of the machine and onto the ground.In both cases, since these large cylindrical compact bales can vary in weight from as much as 850 to 1500 pounds (386 to 682 Kg) or more, quite frequently a bale comes to rest at a position which is within the arc followed by the tailgate when it travels from its open or raised position to its closed or shut position. This means that for both techniques of discharging a completed bale, the discharged bale can interfere with the tailgate as it is closed prior to the machine continuing across the field and initiating the rolling of another bale. Thus, in addition to requiring the operator to take certan manual steps every time a completed bale is to be discharged, there is the additional time consuming possibility that the roll forming machine will have to be pulled forward so that the tailgate can close without having the completed crop roll interfere with its arcuate path of travel.

The foregoing problems are solved, or substantially mitigated, by the present invention which provides a crop roll forming machine and a drive system as defined in the appended claims. The machine according to the present invention has drive means for discharging the completed crop roll automatically with the raising motion of the tailgate. The drive means impart a sufficiently powerful ejective thrust to the completed crop bale as it leaves the roll forming regional to enable it to generally roll clear of the arcuate path of travel followed by the tailgate as it closes.More importantly, the power take-off shaft may continuously be operated during the entire bale discharging sequence, thereby obviating the neces sityforthetimeconsumingstepsofcutting offthe drive to the power take-off shaft and then reengaging it prior to discharge of the completed bale and the recommencing of the roll forming process.

In the preferred crop roll forming machine control means are mounted on a frame and are movable between at least a first position and a second position for cooperative interaction with the drive means and the reversibly rotatable bale forming means to selectively cause the bale forming means to cease being driven in a first direction and cause it to be driven in an opposing second direction when the control means is moved from the first position to the second position so that a completed crop roll is ejected rearwardlyfrom the roll forming machine onto the ground.

A crop roll forming machine according to the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of the crop roll forming machine shown attached to a partially illustrated tractor for towing and having side shielding broken away to show one type of drive means for an upper apron of the machine, Figure 2 is a side elevation of the roll forming machine with a tailgate in the raised position and diamgrammatically illustrates the ejection of a completed bale or crop roll R and the relative positioning of the components of one type of drive means used to effect the reverse movement of the upper apron, Figure 3 is an enlarged side elevation of the drive means of the crop roll forming machine, the components being positioned as in Figure 1 with the tailgate closed and the bale being formed, Figure 4 is a plan view of the drive means and its components corresponding to their positioning in Figure 1, Figure 5 is an enlarged side elevation of the drive means of the crop roll forming machine with its components positioned as in Figure 2 and with the tailgate raised to reverse the path of travel of the upper apron and eject a bale, Figure 6 is a plan view of the drive means of Figure 5 with its components positioned to reverse the path of travel of the upper apron, Figure 7 is a fragmentary view taken on the line 7-7 of Figure 1, showing an input power take-off shaft and a main drive shaft coming from a gearbox on the roll forming machine and leading to the drive means, Figure 8 is an enlarged sectional view taken on the line 8-8 of Figure 4 showing the main drive shaft imparting rotary motion to the upper apron of the bale forming means and a one way clutch mounted thereabout to disengage the drive to the lower apron or transport means, Figure 9 is a sectional view taken on the line 9-9 of Figure 8, Figure 10 is a sectional view taken on the line 10-10 of Figure 2, illustrating lifting means for the tailgate of the crop roll forming machine and its cooperative functioning with tensioning or idler means utilised to effect reversing of the upper apron, Figure 7 7 is an enlarged side elevation of another embodiment of the drive means of the crop roll forming machine, showing in broken lines the positions of its components when the tailgate is in the raised position shown in Figure 2, and in solid lines the positions of its components when the tailgate is in the closed position shown in Figure 1, and Figure 12 is a sectional view taken on the line 12-12 of Figure 11, showing the relative lateral positioning of the components of the drive means of the embodiment of Figure 11.

Referring generally to the drawings and in particularto Figure 1,there is shown a general representation of a crop roll forming machine 10 of the type disclosed in British Patent Specification No.

1,465,644. The crop roll forming machine 10 is illustrated as being fastened to a towing vehicle such as a tractor 11 with a power take-off shaft 12 of the tractor 11 providing the rotary driving force for the mechanically operated components of the crop roll forming machine. The direction of forward travel of the machine 10 is thus towards the left as viewed in Figure 1. The machine 10 is appropriately fastened (by means of a towing hitch 14 mounted on a draft member 15 of the roll forming machine 10) to a hitch member 16 of the tractor 11. Tractor hydraulic lines 18 provide the necessary fluid from the tractor hydraulic reservoir (not shown) for the hydraulically operated components of the roll forming machine 10. The drive meansforthe roll forming machine 10 is indicated generally by the numeral 19.

The roll forming machine 10 shown in Figures 1 and 2 comprises an upper frame 20 and a lower frame 21. The lower frame 21 has mounted on its forward portion a pick-up 22, normally tined, for collcting crop material deposited in preformed windrows on a field and delivering it to the roll forming components of the machine 10. The lower frame 21 includes a horizontal beam member 24 to which is suitably fastened a floor 25. The floor 25 may alternatively be in the form of sheet metal with appropriate channels having conveying chains running therealong, as illustrated in the aforementioned British Patent Specification No. 1,465,644, or may consist of one or more conveyor belts rotatably mounted, or any other means suitable for supporting crop material once it is delivered thereto by the pick-up 22.The horizontal beam member 24 is connected at its forward end to a generally vertical beam member 26. A diagonal brace member 28 is appropriately fastened to the top of the vertical beam member 26 and extends downwardly and rearwardly to its lower end where it is fixedly secured with a bracing member at the rearward portion of a side sheet covering member 29. A diagonal bracing member 30 extends upwardly and forwardly from the rear of the side sheet covering member 29 to its upper end where it is fixedly fastened to the vertical member 26. This lower frame 21 is mounted on a pair of ground-engaging running wheels 31 (only one of which is partially shown) via a suitable axle and support beam indicated generally by the numeral 32.

The upper frame 20, shown in its elevated position in Figure 2, consists of a tailgate pivotable about its mounting point 34 at the top of the vertical member 26. The tailgate or upper frame 20 is formed from a sries of interconnected bracing members 35,36,37, 38, and 39 and is covered by side sheet members 40 and rear sheet members (not shown). The upper frame 20 is raised and lowered by means of a pair of hydraulic cylinders 41, only one of which is shown.

As best seen in Figure 2, the hydraulic cylinders 41 are mounted one on each side of the frame with the cylinder end being fastened at 42 to the vertical beam member 26 of the lower frame 21, and the piston 44 being fastened to the bracing member 35 of the upper frame 20. Suitable hydraulic lines (not shown) are connected to opposite ends of the cylinders 41 to supply the fluid from the aforementioned tractor hydraulic reservoir for the selective activation of the hydraulic cylinders. As bestseen in the elevated position of Figure 2, the upper frame 20 has an elongated section 45 of the type disclosed in the applicants' published British Patent Application No. 2.007,073.

The upper bale forming means or upper apron 46 travels around the periphery of the roll forming machine 10 on a series of appropriately mounted idler sprockets 48,49,50,51 and a drive sprocket (no shown) mounted about a reversible rotatable shaft 52. The shaft 52 is suitably rotatably mounted on the vertical frame member 26. A take-up mechanism indicated generally by the numeral 54 is fastened to bearing brackets 55, shown in Figure 1, which are in turn secured to the upper portion of the vertical member 26. The take-up mechanism 54 further includes a pair of pivotable parallel arms 56, one being positioned on each side of the frame. The take-up mechanism pivots about a bearing 58 and thereby allows the upper apron 46 to be paid out around the periphery of the expanding crop roll R.

The upper apron 46 passes around sprockets 59 mounted on the end of each of the take-up arms 56.

The upper apron 46 preferably comprises a pair of roller link chains (not shown) which are transversely spaced apart on opposing sides of the machine 10 and which are interconnected by a series of spaced, parallel crop-engaging members which combine with the roller link chains to form a rotatable curvilinear crop-engaging surface.

The main features of the roll forming machine are not described in further detail at this point because they are old and well known to one of ordinary skill in the art. It should be noted, however, for the purpose of the embodiment to be described hereinafter, that the upper apron 46 could equally well comprise the aforementioned roller link chains, as well as a series of expandable belts or a series of rollers of cylindrical or hexagonal cross-section arranged to form a movable curvilinear surface.

The drive means 19 is connected to the power take-off shaft 12 (Figure 1) of the tractor 11 through a series of connecting shafts and gearboxes best shown in Figure 7. A connecting shaft 60 is connected to the shaft 12 at a universal joint 62 above the draft member 15. The shaft 60 then joins an input shaft 61 at another universal joint 63. The input shaft 61 is rotatably fastened to the draft member 15 via a support bracket 64, best shown in Figures 1 and 2.

Rearwardly of the bracket 64, the draft member 15 separates into two members 65 and 66 to form an A-frame type of structure. The members 65 and 66 are fixedly fastened to a horizontal support member 68, best shown in Figure 7, which extends transversely across the width of the roll forming machine 10. The input shaft 61 is joined with a right angle gearbox 69 suitably fastened on top of the horizontal member 68. Rotary power is transferred within the gearbox 69 through a set of bevel gears 70 to an output shaft 71. The shaft 71 extends through a side member 72 and at its extremity has mounted thereabout a multi-grooved drive sheave 74. The sheave 74 and output shaft 71 are enabled, as a result of the present invention, to be continuously driven during the operation of the roll forming machine 10 without disengaging the shaft 12.The rotary power being transferred from the power take-off shaft 12 through the gearbox 69 to the sheave 74 is transferred via a drive belt 75 (Figure 3) to a sheave 76 and then to a shaft 78 on which the sheave 76 is mounted.

The transfer of rotary power is best seen in Figures 3 and 5 wherein in enlarged scale the drive means 19 is first shown with the components in position to drive the upper apron 46 in a first direction during the formation of a bale; and secondly in position to drive the upper apron 46 in an opposite second direction during the discharge of the bale. Inwardly of the sheave 76, the shaft 78 has mounted thereon a sprocket 79 which is connected via a chain 80 to a driven pick-up sprocket 81 which is mounted on a pick-up drive shaft 82. The shaft 82 then drives the tined pick-up 22 which is pivotally mounted on the lower frame 21.

The drive sheave 74 also has passed therearound a second driving belt 84 disposed inwardly of the drive belt 75. The belt 84 is wrapped around a multiply grooved driving sheave 85 which is mounted on the reversibly driven shaft 52 and which drives the upper apron 46. Brackets 77 and 106 have belt guide pins extending outwardly over sheaves 74 and 85, respectively, which aid in keeping the belt 84 properly seated around its sheaves. Inwardly of the multiply grooved sheave 85 and coaxially mounted on the shaft 52 is a sprocket 86 around which extends a chain 88. The chain 88 drives the lower apron 89, illustrated in broken lines in Figures 1 and 2.

The drive belt 75 and the driving belt 84 are maintained with the proper amount of tension to transmit rotary power from the output shaft 71 via the drive sheave 74 to both the sheave 76 and the multiply grooved sheave 85 by means of a series of movable tensioning idlers. The relationship of these idlers to the belts 75 and 84 during the roll forming cycle and the roll ejection cycle is shown in Figures 3 and 5, respectively. The drive belt 75 is tensioned by a pair of rotatable idlers 90 and 91 which are movable separately with respect to each other. The idler 90 is rotatably mounted on an arm 92 which is pivotally supported on a side sheet member 94 via a bushing 95 and a pin 96. The idler 91 is fastened to an extensible support arm attached at its upper end to the tailgate 20 (not shown in Figures 3 and 5) and is indicated generally by the numeral 98.A connecting link 93 is pivotally attached to the side sheet member 94 by a bushing 97 and a pin 103. At its opposite end, the link 93 rotatably supports the idler 91 by a bushing 87 and a pin 120. The driving belt 84 is tensioned by a movable idler 99 which is rotatably attached to a second extensible support arm also attached at its upper end to the tailgate 20 and indicated generally by the number 100. The idler 90 is spring biased by a spring 101 which is fastened via a suitable clevis 102 mounted on a bracket 104. The bracket 104 is fixedly fastened to the side sheet member 94. The spring 101 serves to keep the belt 75 under the proper amount of tension to transmit rotary drive power when the upper frame or tailgate 20 is in the closed position and a crop roll R is being formed within the machine in a region commonly known as the bale forming region.A spring 105, one end of which is anchored on a bracket 106, serves to relieve the tension in the belt 84 by lifting the idler 99 as the tailgate 20 is elevated beyond a predetermined point in its arcuate path to the raised or open position.

The extensible support arms 98 and 100 are shown in more detail in Figure 10. The arm 100 is fastened at its upper end to the bracing member 35 of the upper frame or tailgate 20 by a stub pin 108 and bushing 109, both of which are inserted through a suitably sized opening in a coupling extension 110.

The support arm 100 has an upper base member 111 with a spring 112 inserted within its hollow upper portion. The opposite end of the arm 100 has inserted therein a telescoping portion 114 which has at its lower end a bracket 115 suitably fastened thereto. The idler 99 is rotatably mounted around a roller pin 116 which passes through spaced side flanges of the bracket 115. The spring 112 serves, through the idler 99, to keep sufficient tension in the belt 84 to permit the transfer of rotary drive power when the tailgate 20 is in the closed position.

The support arm 98 is similarly mounted on the pin 108 and bushing 109 at the upper portion of a base member 118 of the arm 98. Inserted within the hollowed lower end of the base member 118 is a telescoping portion 119. The lower end of the telescoping portion 119 has a roller pin 120 fixed thereto and about which the idler 91 is rotatably mounted. The external or outboard end of the roller pin 120 has the connecting link 93 fixed thereto. The telescoping portions 114, 119 of the support arms 100 and 98 are movable within the base members 111 and 118, respectively, to permit some lost motion to occur in the movement of the idlers 99 and 91 as the tailgate is raised. This permits the required amount of tension to be maintained on the belts 75 and 84 until certain predetermined points in the elevational path of the tailgate are reached.The arcuate movement of the tailgate, in conjunction with the spring 105, causes the idler 99 to be sufficiently raised to reduce the required tension to interrupt the transfer of the rotary drive power of the belt 84. The belt 75 is continuously maintained under tension as the tailgate 20 is raised by the cooperative pivotal effect of the idlers 90 and 91 and the spring 101 so that rotary driving force is continuously transferred from the sheave 74 to the sheave 76. As the tailgate continues to be raised towards its fully extended position, a second predetermined point is reached where the arm 98 is in a position which causes the idler 91 to pull the drive belt 75 sufficiently upwardly and rearwardly that it back wraps about multiply grooved sheave 85.The combined cooperative effect of the idlers 90, the spring 101 and the arm 98 creates greater tension on the back wrapped drive belt 75 when the tailgate is in the raised position than when it is in the lowered or closed position. The effect of this back wrapping will be further explained hereinafter.

A stop pin 121 is fastened to and extends outwardly from the side sheet member 94 to engage a pivot arm 107, thereby limiting the amount of upward rotational movement of the idler 99 when the tailgate is in the raised position. A support shelf 122 is suitably fixed to the side sheet member 94 to support the lower run of the driving belt 84 when the tailgate is raised beyond the predetermined point that removes the tension from the driving belt 84 to interrupt the transfer of rotary power between the drive sheave 74 and the multiply grooved sheave 85.

Figure 11 shows an alternative embodiment of the drive means indicated generally by the numeral 19 in Figure 1. Rotary power is transferred to the shaft 71 and then to the sheaves 74 and 85 via the driving belt 84 as explained previously. In this embodiment, however, the drive belt 75 is connected directly to the sheave 76 (not shown) without the use of any intermediate idlers. The driving belt 84 is tensioned by the idler 99 fastened to the tailgate in the manner previously described. The shaft 52 has one end of a support arm 139 pivotally mounted thereabout. On its opposite end, the support arm 139 rotatably supports a sheave 140 mounted about a roller pin 141. A belt 142 passes around the sheave 140 on the swingable end of the support arm 139 and around a sheave 144 on the pivoted end.The support arm 139 is at a point suitably located along its length, attached to a lifting arm 145. The lifting arm 145 is fastened to the tailgate about the stub pin 108 (not shown) coaxially with extensible support arms 100 (not shown) and hydraulic cylinder 41 (not shown).

This mounting relationship is essentially as illustrated in Figure 10 with the exception of the lifting arm 145 and its accompanying elements replacing the extensible arm 98 and its elements. The support arm 139 and the lifting arm 145 are biased downwardly by a spring 146 which is fastened via a bracket 148 to the side sheet member 94.

The sheave 140 on the swingable end of the support arm 139 is designed to contact the cast iron frictional extended surface 149 of the sheave 74, as shown in Figure 12. Preferably, the sheave 140 has rubber coated flanged sides or cylindrical tyre-type edge extensions which would increase the friction between the engaging surfaces of the sheaves 140 and 74 to promote the transfer of rotary power when the lifting arm 145 is raised by the upward motion of the tailgate 20. The raising of the arm 145 causes the support arm 139 to pivot upwardly and bring the sheave 140 and its cooperating belt 142 into contact with the surface 149 of the sheave 74. If desired, a lost motion design, such as that shown in extensible suport arm 100 in Figure 10, could be incorporated in the lifting arm 145.

A one-way clutch (or unidirectional drive mechanism) 124 is mounted within the multiply grooved sheave 85. The clutch 124, best shown in Figures8 and 9, couples the sheave 85 and the sprocket 86.

The sprocket 86 is fastened by bolts 125 to a hub 126a rotatably mounted on the shaft 52. The sheave 85 has a hub 126 having a pawl or dog 129 fastened to it by a pin 130. The pawl is spring biased radially outwardly by a compression spring 131 inserted in a suitable slot cast in the hub 126. The hub 126a has a cup-like end which is within the sheave 85 and has ratchet teeth 128 circumferentially cast about its entire inner circumference. The ratchet teeth 128 cooperate with the pawl 129 so that when the sheave 85 is rotated in a counterclockwise direction (as viewed in Figures 3, 5 and 8), the clutch is disengaged and the pawl 129 rides over the ratchet teeth 128 so that the sprocket 86 is not driven. When the sheave 85 rotates in a clockwise direction, the pawl 129 engages the ratchet teeth 128 and causes the sprocket 86 to rotate.The rotation of the sprocket 86 causes the lower apron chain 88 to be driven and accordingly drives the lower apron 89, briefly shown in Figures 1 and 2. The end of the shaft 52 is splined and interengageswith the splined centre of the sheave 85. the sheave 85 is securely fastened on the shaft 52 by a locking bolt 135 and washer 136, or in any other suitable fashion. Thus, the clutch 124 is operative to transmit unidirectional motion from the sheave 85 to the sprocket 86.

Alternatively, the interior of the hub 126 could be provided with ratchet teeth 128 circumferentially cast about the entire interior circumference of the sheave 85. The ratchet teeth 128 would then cooperate with the pawl or dog 129 fastened to a hub (like hub 126a) by the pin 130. In this configuration, when the sheave 85 is rotated in a clockwise direction, the clutch would be disengaged and the pawl 129 would ride over the ratchet teeth 128. A driving relationship would exist between the ratchet teeth 128 and the pawl 129 when the sheave 85 turns in a counterclockwise direction.

In operation, the crop roll forming machine 10 is towed across a field that has arranged thereon in preformed windrows a suitable crop material that has been previously cut. The tined pick-up 22 gathers the windrowed crop material, picks it up from the ground and transports it upwardly into the forward portion of the floor 25. The crop material is then transported by the lower apron 89 rearwardly into contact with the moving upper apron 46. The upper apron 46 causes the crop material to be rolled at the rear of the floor 25 in what is commonly called the bale forming region and initiates the formation of a core of crop material. The crop material is continually fed into the bale forming region into a cylindrically shaped core of ever increasing diameter.The upper apron 46 expands about the crop R as the latter increases in size by means of the rotation of the take-up means 54 which permits the paying out of more of the upper apron 46 to accommodate the increased bale size. Once the crop roll R has reached the desired size, the operator stops the machine 10 and, if desired, wraps the roll R with a wrapping or binding material. Upon completion of the roll forming and wrapping cycles, the operator elevates the upper frame or tailgate 20 in preparation for discharging the completed crop roll R onto the ground.

Initially while the upper frame 20 is being raised the support arms 98 and 100 maintain sufficient pressure on the idlers 91 and 99 to cause the belts 75 and 84 to continue to transfer rotary force. However, beyond first predetermined points in the elevation of the upper frame 20, the lost motion built into the telescoping portion 119 of the support arm 98 reaches its limit and the idler 91 begins to be raised sufficiently to affect the manner in which the transfer of rotary power through the belt 75 is achieved.

Similarly, at a second predetermined point in the elevation of the upper frame 20, the tension spring 112 reaches its limit of expansion and the idler 99 begins to be raised, thereby decreasing the tension in the driving belt 84 until it causes the sheave 85 to cease to be driven. This in turn stops the rotation of the shaft 52 which is connected to the sprocket 138 which drives the upper apron 46. As the tailgate or upper frame 20 continues to be raised, the idler 91 on the lower end of the support arm 98 is pivoted upwardly and rearwardly about the pivot point of the connecting link 93. This pivotal motion of the idler 91 in turn causes the idler 90 to be pivoted upwardly in a generally clockwise rotation (as viewed in Figures 3 and 5) about the pivot pin 96 of the idler arm 92.

During this entire time, rotary drive continues to be transmitted via the drive belt 75 from the drive sheave 74 to the sheave 76. At the first predetermined point in the elevation of the tailgate or upper frame 20, the idler 91 is pulled sufficiently upwardly and rearwardly to cause the belt 75 to begin to back wrap about the now stationary sheave 85. Once the belt 75 is back wrapped about the sheave 85 with sufficient tension, the continued movement of the belt 75 imparts a counterclockwise motion (as viewed in Figures 3 and 5) to the sheave 85, thereby causing the one-way clutch 124 to disengage as the pawl 129 rides over the ratchet teeth 128.Because of the splined connection of the sheave 85 on the shaft 52, the shaft 52 also rotates in a counterclockwise direction, transmitting this rotary drive to the sprock et 138 about which is mounted one of the chains of the upper apron 46. The counterclockwise rotation of the sprocket 138 causes the upper apron 46 to reverse its normal direction of travel, as indicated by the arrow Yin Figure 2, and imparttopspin to the complete crop roll R as it urges the roll R out of the bale forming region of the machine. Upon completion of the ejection of the completed crops roll R, the upper frame or tailgate 20 is lowered, thereby causing the idlers 99 and 91 to be driven generally downwardly and forwardly into the position generally shown in Figure 3. As the idler 91 is lowered, it causes the belt 75 to lose contact with the sheave 85 and, therefore, allows the upper apron 46 to cease turning in its reverse direction. As the idler 99 is lowered with the closing of the tailgate or upper frame 20, it comes into contact again with the belt 84 and supplies sufficient tension to permit the rotary drive force to be transferred from the continuously turning sheave 74 to the sheave 85 via the belt 84 so that the sheave 85 drives the shaft 52 in a clockwise direction. This allows the upper apron 46 to be driven in the direction illustrated by the arrow X in Figure 1.

The drive means 19 shown in the alternative embodiment in Figures 11 and 12 functions during operation of the roll forming machine 10 in much the same way as what has just been described. Initiaily, while the upper frame or tailgate 20 is being raised the support arm 100, with its telescoping portion 114, maintains sufficient pressure through the idler 99 on the belt 84 to continue the transfer of rotary power between the sheaves 74 and 85. As explained above, beyond the first predetermined point in the elevation of the upper frame 20 the lost motion provided by the telescoping portion 114 of the support arm 100 reaches its limit and the idler 99 is raised until there is insufficient tension in the driving belt 84 to cause the rotation, thereby stopping the drive of the upper apron 46 in its first driven direction.As the tailgate or upper frame 20 is raised, the lifting arm 145 moves upwardly, thereby causing the support arm 139 to pivot about the shaft 52 and raise the idler 140 on its opposing end. At a second predetermined point in the elevation ofthetailgate or upper frame 20, the sheave 140 with its belt 142 is brought into contact with the frictional surface 149 of the continuously turning sheave 74. Atthis point in the elevation of the tailgate 20, the rotary power from the shaft 71 is transmitted through the sheave 74 to the sheave 140 and then to the belt 142. The frictional engagement of the surface 149 with the belt 142 and the sheave 140 imparts a counterclockwise rotation to the belt 142 which in turn causes the sheave 44 to the drive shaft 52 in the reverse direction.The one way clutch 124 permits the shaft 52 to turn without driving the sprocket 132. Thus, the lower apron 89 remains declutched while the upper apron is driven in reverse direction when the tailgate is raised. This reverse travel of the upper apron 46 (in the direction of arrow Y) imparts a topspin to the completed crop roll R, as shown generally in Figure 2, and causes the bale automatically to be ejected from the roll forming machine 10. During this time, the shaft 71 and sheave 76 with its mounted belt 75 are continuously driven.

Thus, during the entire discharge operation of the roll forming machine 10, the operator only has to perform two steps manually. The operator must elevate the tailgate to cause the upper apron initially to cease movement before the upper apron is automatically reversed in its direction of travel to imparttopspin to the complete crop roll to eject it.

Then the operator must manually actuate the controls to close the tailgate which automatically stops the reverse movement of the upper apron 46 and permits it to be driven in its forward direction prior to recommencing the bale forming operation. There is no need to disengage and then re-engage the power take-off shaft since the power take-off has been able to operate continuously throughout the entire dis charge operation.

Thus, the described crop roll forming machine automatically discharges a completed crop roll from the bale forming region, this being activated by the raising of the tailgate. The machine has a drive system which cooperates with the movement of the tailgate so that at a predetermined point the bale forming means automatically ceases its rotation in a first direction and at another predetermined point in the movement of the tailgate reverses its rotation to eject the completed crop roll. The power take-off shaft or rotary power shaft coming from the prime moving or towing vehicle need not be stopped during the bale forming and ejecting cycle.The improved drive system uses a continuously moving rotary power transfer means to backwrap about a suitable receiving element on the drive shaft of the bale forming means to reverse the direction of rotation of the bale forming means in response to the movement of the tailgate.

It is an advantage of the described machine that a completed crop roll is positively ejected outthe rear of the roll forming machine from the bale forming region by the action of the bale forming means imparting topspin to the crop roll by the reversal in direction of travel of the bale forming means, thereby permitting the roll to leave the machine with sufficient force to permit it to come to rest beyond the path of the closing tailgate. Also, the lower apron or lower conveyor is automatically declutched in conjunction with the movement of the tailgate upwardly. The amount of manual participation by the roll forming machine operator is significantly reduced and the total amount of time necessary to discharge a completed crop roll and recommence the forming of an additional bale is substantially decreased.

The embodiments described herein with reference to the accompanying drawings are similar to the embodiments disclosed in the applicants' copending British Patent Application No.8010198 (Serial No. 2045155) of even date.

Claims

1. A crop roll forming machine having a mobile frame, a pick-up mounted on the frame, a bale forming region adjacentthe pick-up and bale form ing means rotatably mounted on the frame so as to move along a predetermined path of travel, wherein the machine additionally comprises drive means which are connected to the bale forming means and which are selectively actuatable to drive the bale forming means in a first direction along the path of travel during the formation of the bale and, at a desired point in the formation of the bale, operable to stop driving the bale forming means in the first direction and reverse the drive to the bale forming means so that the latter move in an opposing second direction, to eject the bale from the bale forming region.

2. A crop roll forming machine for forming cylindrical bales of crop material, comprising: (a) a generally upright mobile frame having opposing sides with an infeed area and an outlet area therebetween, the frame being adapted to travel across a field of crop material; (b) a pick-up mounted on the frame to gather crop material from the field and deliver it to the infeed area; (c) bale forming means rotatably mounted on the frame and movable in a predetermined path of travel, the bale forming means being rotatable along the path of travel in a first direction and being reversible to rotate to an opposing second direction and defining in combination with the infeed and outlet areas a bale forming region; (d) drive means rotatably mounted on the frame;; (e) control means mounted on the frame and movable between at least a first position and a second position for cooperative interaction with the drive means and the bale forming means to selectively cause the bale forming means to cease to be driven in the first direction and cause it to be driven in the opposing second direction when the control means is moved from the first position to the second position so that a completed crop bale is ejected rearwardlyfrom the bale forming region through the outlet area onto the ground.

3. A roll forming machine according to claim 2, wherein the control means further comprises tensioning means and lifting means mounted on the frame.

4. A roll forming machine according to claim 3, wherein the tensioning means further comprises belt means connectable to the drive means and at least one movable idler rotatably mounted on the frame so as to cooperate with the belt means to maintain the proper amount of tension to permit the transfer of rotary power between the drive means and the bale forming means.

5. A roll forming machine according to claim 4, wherein the lifting means further comprises a pivotable support arm having a first end and a second end with a rotatable contact element mounted on the second end, the contact element being connectable to the bale forming means.

6. A roll forming machine according to claim 5, wherein the lifting means further comprises a lifting link connectable to the pivotable support arm and a hydraulic cylinder so that when the lifting link is raised by the hydraulic cylinder the contact element is brought into driven engagement with the drive means to effect the reversal of the path of travel of the bale forming means from the first direction to the opposing second direction by the transfer of rotary power via the belt means.

7. A roll forming machine according to claim 5 or 6, wherein the contact element comprises a generally cylindrically shaped roller with a peripheral frictionally engaging surface.

8. Acrop roll forming machineforforming generally cylindrical bales of crop material, comprising: (a) a generally upright mobile frame having opposing sides with an infeed area and an outlet area therebetween, the frame being adapted to travel across a field of crop material; (b) a pick-up mounted on the frame to gather crop material from the field and deliver it to the infeed area; (c) bale forming means rotatably mounted on the frame and movable in a predetermined path of travel, the bale forming means being rotatable in a first direction and being reversible to rotate in an opposing second direction and defining in combination with the infeed and outlet areas a bale forming region; (d) drive means rotatably mounted on the frame for driving the pick-up and the bale forming means;; (e) tensioning means mounted on the frame and cooperable with the drive means, the tensioning means being movable between at least a first position thereof and a second position thereof; and (f) lifting means mounted on the frame for selectively moving the tensioning means between the first position, wherein the bale forming means is driven in the first direction, and the second position, wherein the bale forming means is driven in the opposing second direction, so that a completed crop bale is thereby ejected rearwardly from the bale forming region through the outlet area onto the ground.

9. A roll forming machine according to claim 8, wherein the bale forming means comprises at least one rotatably mounted belt.

10. A roll forming machine according to claim 8, wherein the bale forming means comprises a plurality of adjacent cylindrical surfaces rotatably mounted on the frame.

11. A roll forming machine according to claim 8, wherein the bale forming means further comprises a pair of chains interconnected by parallel, spaced horizontal members forming a generally curvilinear crop engaging surface.

12. A roll forming machine according to claim 8, wherein the drive means further comprises belt means drivingly connected to rotary drive means.

13. A roll forming machine according to claim 12, wherein the tensioning means further comprises at least one movable idler rotatably mounted on the frame so as to cooperate with the belt means to maintain the proper amount oaf tension to permit the transfer of rotary power between the drive means and the bale forming means.

14. A roll forming machine according to claim 13, wherein the lifting means further comprises a pivotable support arm having a first end and a second end with a rotatable contact element mounted on the second end, the contact element being connectable to the bale forming means.

15. A roll forming machine according to claim 14, wherein the lifting means further comprises a hydraulic cylinder and a lifting link having a first end connected to the pivotable support arm and a second end connected to the hydraulic cylinder so that when the lifting link is raised by the hydraulic cylinder the contact element is brought into driven engagement with the drive means to effect the reversal of the path of travel of the bale forming means by the transfer of rotary power via the belt means.

16. A roll forming machine according to claim 15, wherein the contact element comprises a generally cylindrically shaped roller with a peripheral frictionally engaging surface.

17. A roll forming machine for forming cylindrical bales of crop material comprising: (a) a generally upright mobile frame having opposing sides with an infeed area and an outlet area therebetween, the frame being adapted to travel across a field of crop material; (b) a pick-up mounted on the frame to gather crop material from the field and deliver it to the infeed area; (c) a movable transport means disposed adjacent the pick-up and between the opposing sides for receiving the crop material from the pick-up in the infeed area and moving it generally rearwardly towards the outlet area; (d) bale forming means movably mounted on the frame above the transport means and defining therebetween a bale forming region, the bale forming means being movable in a first direction and being reversible to move in an opposing second direction;; (e) a tailgate pivotally mounted on the opposing sides of the frame above the bale forming region and movable in a generally arcuate path of travel between a closed position wherein the outlet area is obstructed and an open position wherein the outlet area in obstructed to permit the ejection of a bale; (f) drive means rotatably mounted on the frame for driving the pick-up, the transport means and the bale forming means, (g) lifting means mounted on the frame and connected to the tailgate for selectively moving the tailgate between the closed position and the open position; and (h) tensioning means movably mounted on the frame and cooperable with the drive means such that when the tailgate is raised through the path of travel to the open position, the tensioning means interact with the drive means to stop driving the transport means and to cause the bale forming means to stop its movement in the first direction and begin moving in the opposing second direction so that a completed crop bale is ejected rearwardly from the bale forming region through the outlet area onto the ground.

18. A roll forming machine according to clam 17, wherein the drive means further comprises a drive shaft, a reversibly driven shaft, a first drive belt connecting the driving shaft and the reversibly driven shaft, and a second drive belt passing around the reversibly driven shaft.

19. A roll forming machine according to claim 18, wherein the tensioning means further comprises at least one rotatable idler mounted on a movable support arm fastened to the frame.

20. A roll forming machine according to claim 19, wherein the lifting means comprises at least one hydraulic cylinder having a first end and a movable second end, the first end being fastened to the frame and the second end being connected to the movable support arm.

21. A roll forming machine according to claim 20, wherein the tensioning means further comprises a contact element rotatably mounted on a pivotable support arm mounted on the frame and connectable to the reversibly driven shaft so that when the tailgate is raised ot the open position the contact element is brought into driven engagement with the driving shaft and the rotatable idler is disengaged from the first drive belt, thereby causing the bale forming means to stop its movement in the first direction and begin moving in the second direction so that a completed crop roll is ejected rearwardly from the bale forming region through the outlet area onto the ground.

22. A roll forming machine according to claim 21, wherein the contact element further comprises a generally cylindrically shaped roller with a peripheral frictionally engaging surface.

23. A roll forming machine according to claim 17, wherein the bale forming means comprises at least one belt rotatably mounted on the frame.

24. A roll forming machine according to claim 17, wherein the bale forming means further comprises a plurality of cylindrical adjacently mounted surfaces rotatably mounted on the frame.

25. A roll forming machine according to claim 17, wherein the bale forming means further comprises a pair of chains interconnected by parallel, spaced horizontal members forming a generally curvilinear crop-engaging surface.

26. A roll forming machine according to claim 17, wherein the movable transport means comprises at least one rotatable cylinder rotatably mounted on the opposing sides of the frame.

27. A roll forming machine according to claim 16, wherein the movable transport means comprises at least one rotatable belt rotatably mounted on the opposing sides of the frame.

28. A roll forming machine according to claim 17, wherein the movable transport means comprises a series of longitudinally extending, spaced chains rotatably mounted within fore-and-aft extending channels, the channels being set within a generally horizontally positioned floor member, the chains further having generally vertically extending crop engaging elements spaced therealong.

29. A drive system having a frame, a rotary powered drive source, and a reversible rotatably driven working element which is supported by the frame, the drive system comprising: (a) a rotary driving shaft connected to the drive source and rotatably mounted on the frame; (b) a first driven shaft rotatably mounted on the frame; Ic) a second driven reversible shaft rotatably mounted on the frame; (d) a first rotary drive transfer means intercon necting the driving shaft and the first driven shaft; (e) a second rotary drive transfer means inter connecting the driving shaft and the second driven reversible shaft to selectively drive the working element and the second driven reversible shaft in a first direction or an opposing second direction;; (f) a first rotatable tensioning means movably fastened to the frame for cooperatively interacting with the second rotary drive transfer means so that sufficient tension is selectively maintainable on the second rotary drive transfer means to permit the rotary driving shaft to drive the second driven reversible shaft in the first direction; (g) second rotatable tensioning means pivotally fastened to the frame for cooperatively interacting with the first rotary drive transfer means so that sufficient tension is maintained thereon to permit the rotary driving shaft to drive the first driven shaft; and (h) lifting means mounted on the frame and connected to the first rotatable tensioning means and the second rotatable tensioning means in such a manner that when actuated the lifting means moves the first rotatable tensioning means and the second rotatable tensioning means so that the second rotary drive transfer means no longer transmits rotary power from the driving shaft to the second driven reversible shaft and the first rotary drive transfer means at a predetermined point in the movement of the second rotatable tensioning means causes rotary power to be transmitted to the second driven reversible shaft to drive the second driven reversible shaft and the working element in the opposing second direction.

30. A drive system according to claim 29, wherein the first rotary drive transfer means further comprises a drive belt rotatably mounted about the rotary drving shaft and the first driven shaft.

31. A drive system according to claim 30, wherein the second rotary drive transfer means further comprises a drive belt rotatably mounted about a sheave mounted on the driving shaft and the second driven reversible shaft.

32. A drive system according to claim 31, wherein the first rotatable tensioning means further comprises a rotatable idler mounted on a movable arm mounted on the frame.

33. A drive system according to claim 32, wherein the second rotatable tensioning means comprises at least a pair of rotatable idlers mounted on separate arms.

34. A drive system according to claim 33, wherein the lifting means comprises a hydraulic cylinder connected to the arm of the first rotatable tensioning means and the frame.

35. A drive system having a rotary powered drive source, a first reversible rotatably driven working element, a second rotatably driven working element and a frame supporting the first and second working elements, the system comprising: (a) a rotary driving shaft connected to the drive source and rotatably mounted on the frame; (b) a first driven shaft rotatably mounted on the frame and connectable to the driving shaft; (c) a second driven reversible shaft rotatably mounted on the frame and connectable to the driving shaft and the working elements; (d) first rotary drive transfer means connectable to the driving shaft and the first driven shaft;; (e) second rotary drive transfer means connectable to the driving shaft and the second reversible shaft to selectively drive the first and second working elements and the second driven reversible shaft in a first direction and selectively drive the first reversible rotatably driven working element and the second driven reversible shaft in a second direction opposite to the first direction; (f) first rotatable tensioning means movably mounted on the frame and cooperable with the second rotary drive transfer means so that sufficient tension is selectively maintainable on the second rotary drive transfer means to permit the rotary driving shaft to drive the second driven reversible shaft;; (g) second rotatable tensioning means pivotally fastened to the frame and cooperable with the first rotary drive transfer means so that sufficient tension is maintained thereon to permit the rotary driving shaft to drive the first driven shaft.

(h) clutching means mounted about the second driven reversible shaft, connected to the second working element and effective when engaged to transfer rotary power to the second working element and when disengaged not to transfer rotary power to the second working element; and (i) lifting means mounted on the frame and connected to the first rotatable tensioning means and the second rotatable tensioning means in such a manner that when actuated the lifting means moves the first rotatable tensioning means and the second rotatable tensioning means so that the second rotary drive transfer means no longer transmits rotary power from the driving shaft to the second driven reversible shaft and at a predetermined point in the movement of the second rotatable tensioning means the first rotary drive transfer means causes rotary power to be transmitted to the second driven reversible shaft to drive the second driven reversible shaft and the first working element in the opposing second direction, the rotation of the second driven reversible shaft in the opposing second direction further causing the clutching means to disengage and stop the transfer of rotary power to the second working element.

36. A drive system according to claim 35, wherein the first rotary drive transfer means further comprises a first drive belt rotatably mounted about the rotary driving shaft and the first driven shaft.

37. A drive system acccording to claim 36, wherein the second rotary drive transfer means further comprises a second drive belt rotatably mounted about the rotary driving shaft and the second driven reversible shaft.

38. A drive system according to claim 37, wherein the first rotatable tensioning means further comprises a rotatable idler mounted on a movable arm mounted on the frame.

39. A drive system according to claim 38, wherein the second rotatable tensioning means comprises at least a first rotatable idler and a second rotatable idler, the first idler being mounted on a first pivotable arm and the second idler being mounted on a second pivotable arm.

40. A drive system according to claim 39, wherein the clutching means further comprises a one-way overriding clutch rotatably mounted about the second driven reversible shaft and rotatably connected to the second drive belt.

41. A drive system according to claim 35, wherein the lifting means further comprises a hydraulic cylinder connected to the arm of the first rotatable tensioning means and the frame.

42. Acrop roll forming machine for forming cylindrical bales of crop material having a generally upright mobile frame, a pick-up mounted on the frame, bale forming means rotatably mounted on the frame, the bale forming means being movable in a first direction and being reversible to move in an opposing second direction, a rotary powered drive means, and a drive system having:: (a) a rotary driving shaft connected to the drive means and rotatably mounted on the frame; (b) a first driven shaft rotatably mounted on the frame and connectable to the drive shaft; (c) a second driven reversible shaft mounted on the frame and connectable to the driving shaft and the bale forming means; (d) first rotary drive transfer means connectable to the driving shaft and the first driven shaft; (e) second rotary drive transfer means connectable to the driving shaft and the second driven reversible shaft to selectively drive the bale forming means and the second driven reversible shaft in the first direction on the opposing second direction;; (f) first tensioning means movably mounted on the frame and cooperable with the second rotary drive transfer means so that sufficient tension is selectively maintainable on the second rotary drive transfer means to permit the driving shaft to drive the second driven reversible shaft; (g) second tensioning means pivotally mounted on the frame and cooperable with the first rotary drive transfer means so that sufficient tension is maintained thereon to permit the driving shaft to drive the first driven shaft; and (h) lifting means mounted on the frame and connected to the first tensioning means and the second tensioning means in such a manner that when actuated the lifting means moves the first tensioning means and the second tensioning means so that the second rotary drive transfer means no longer transmits rotary power from the driving shaft to the second driven reversible shaft and at a predetermined point in the movement of the second tensioning means the first rotary drive transfer means causes rotary power to be transmitted to the second driven reversible shaft to drive the second drive reversible shaft and the bale forming means in the opposing second direction to eject a completed crop bale from the machine.

43. A roll forming machine according to claim 42, wherein the first rotary drive transfer means comprises a first drive belt rotatably mounted about the driving shaft and the first driven shaft.

44. A roll forming machine according to claim 43, wherein the second rotary drive transfer means comprises a second drive belt rotatably mounted about the driving shaft and the second driven reversible shaft.

45. A roll forming machine according to the claim 44, wherein the first tensioning means comprises an idler rotatably mounted on a movable arm mounted on the frame.

46. A roll forming machine according to claim 45, wherein the second tensioning means comprises at least a first rotatable idler and a second rotatable idler, the first idler being mounted on a first pivotable arm and the second idler being mounted on a second pivotable arm.

47. A roll forming machine according to claim 46 wherein the second tensioning means comprises at least one hydraulic cylinder connected to the movable arm of the first tensioning means.

48. A roll forming machine according to claim 42, wherein the bale forming means further comprises an upper apron presenting a rotatable curvilinear bale-engaging surface and a transport means adjacent the pick-up and rotatably mounted on the frame generally below the upper apron for supporting crop material as it is formed into a crop bale.

49. A roll forming machine according to claim 48, wherein the drive system further comprises a oneway overriding clutch rotatably mounted on the second driven reversible shaft and rotatably connected to the second rotary drive transfer means, the clutch being operable when engaged to transfer rotary power to the transport means and when disengaged not to transfer rotary power to the transport means.

50. A crop roll forming machineforforming cylindrical bales of crop material, comprising: (a) a generally upright mobile frame having opposing sides, an infeed area and an outlet area therebetween, the frame being adapted to travel across afield of crop material; (b) a pick-up mounted on the frame to gather crop material from the field and deliver itto the infeed area; (c) bale forming means rotatably mounted on the frame and movable in a predetermined path of travel, the bale forming means being rotatable in a first direction and being reversible to rotate in an opposing second direction and defining in combination with the infeed and outlet areas a bale forming region; (d) drive means rotatably mounted on the frame, (e) a rotary driving shaft connected to the drive means and rotatably mounted on the frame;; (f) a first driven shaft rotatably mounted on the frame; (g) a second driven reversible shaft rotatably mounted on the frame; (h) a first rotary drive transfer means interconnecting the driving shaft and the first driven shaft; (i) a second rotary drive transfer means interconnecting the driving shaft and the second driven reversible shaft to selectively drive the bale forming means and the second driven reversible shaft in the first direction or the opposing second direction;; (j) a first rotatable tensioning means mounted on the frame and movable between at least a first position and a second position for cooperatively interacting with the second rotary drive transfer means so that sufficient tension is selectively maintainable on the second rotary drive transfer means to permit the rotary driving shaft to drive the second driven reversible shaft in the first direction; (k) second rotatable tensioning means pivotally mounted on the frame and movable between at least a first position and a second position for cooperatively interacting with the first rotary drive transfer means so that sufficient tension is maintained thereto to permit the rotary driving shaft to drive the first driven shaft; and (I) lifting means mounted on the frame and connected to the first rotatable tensioning means and the second rotatable tensioning means in such a manner that when actuated the lifting means moves the first rotatable tensioning means and the second rotatable tensioning means between the first positions wherein the bale forming means is driven in the first direction and the second positions so that the second rotary drive transfer means no longer transmits rotary power from the driving shaft to the second driven reversible shaft and the first rotary drive transfer means at the second position in the movement of the second rotatable tensioning means causes rotary power to be transmitted to the second driven reversible shaft to drive the second driven reversible shaft and the bale forming means in the opposing second direction to eject a completed crop bale from the bale forming region.

51. A roll forming machine according to claim 50, wherein the bale forming means further comprises an upper apron presenting a rotating curvilinear bale-engaging surface and a transport means adjacent the pick-up and rotatably mounted on the frame generally below the upper apron for supporting crop material as it is formed into a crop bale.

52. A roll forming machine according to claim 23, wherein the drive means further comprises a oneway overriding clutch rotatably mounted on the second driven reversible shaft and rotatably connected to the second rotary drive transfer means, the clutch being operable when engaged to transfer rotary power to the transport means and when disengaged not to transfer rotary power to the transfer means.

53. A crop roll forming machineforforming cylindrical bales of crop material, comprising: (a) a generally upright mobile frame having opposing sides, an infeed area and an outlet area therebetween, the frame being adapted to travel across a field of crop material; (b) a pick-up mounted on the frame to gather crop material from the field and deliver it to the infeed area; (c) a movable transport means adjacent the pick-up and between the opposing sides for receiving the crop material from the pick-up in the infeed area and moving it generally rearwardly towards the outlet area; (d) a bale forming means rotatably mounted on the frame above the transport means and defining therebetween a bale forming region, the bale forming means being reversibly rotatable in a first direction and an opposing second direction;; (e) a tailgate pivotally mounted on the opposing sides of the frame about the bale forming region and being movable in a generally arcuate path of travel between a closed position wherein the outlet area is obstructed and an open position wherein the outlet area is unobstructed to permit the ejection of a bale; (f) drive means rotatably mounted on the frame; (g) a rotary driving shaft connected to the drive means and rotatably mounted on the frame; (h) a first driven shaft rotatably mounted on the frame and connectable to the driving shaft; (i) a second driven reversible shaft rotatably mounted on the frame and connectable to the driving shaft and the bale forming means; (j) first rotary drive transfer means connectable to the driving shaft and the first driven shaft;; (k) second rotary drive transfer means connectable to the driving shaft and the second driven reversible shaft to selectively drive the bale forming means and the second driven reversible shaft in the first direction and the opposing second direction; (I) first rotatable tensioning means movably mounted on the frame and cooperable with the secondary rotary drive transfer means such that sufficient tension is selectively maintainable on the second rotary drive transfer means to permit the rotary driving shaft to drive the second driven reversible shaft; (m) second rotatable tensioning means pivotally mounted on the frame and cooperable with the first rotary drive transfer means so that sufficient tension is maintained thereon to permit the rotary driving shaft to drive the first driven shaft;; (n) lifting means mounted on the frame and connected to the tailgate for selectively moving the tailgate between the closed position and the open position, the lifting means further being connected to the first rotatable tensioning means and the second rotatable tensioning means in such a manner that when actuated the lifting means moves the first rotatable tensioning means and the second rotatable tensioning means so that the second rotary drive transfer means no longer transmits rotary power from the driving shaft to the second driven reversible shaft and at a predetermined point in the movement of the second rotatable tensioning means the first rotary drive transfer means causes rotary power to be transmitted to the second driven reversible shaft to drive the second driven reversible shaft and the bale forming means in the opposing second direction to eject a completed crop bale from the bale forming region.

54. A roll forming machine according to claim 53, wherein the drive means further comprises a oneway overriding clutch rotatably mounted on the second driven reversible shaft and rotatably connected to the second rotary drive transfer means, the clutch being operable when engaged to transfer rotary power to the transport means and when disengaged not to transfer rotary power to the transport means.

55. A drive system according to claim 29 or 35, substantially as herein particularly described with reference to Figures 1 to 10, oras modified by Figures 11 and 12, of the accompanying drawings.

56. A crop roll forming machine constructed and arranged substantially as herein particularly described with reference to Figures 1 to 10, or as modified by Figures 11 and 12, of the accompanying drawings.