BALE WRAPPING MACHINE

Abstract: A machine for wrapping cylindrical bales comprises an open-fronted wheeled frame (2) for attachment to a towing vehicle, a roller (26) extending transversely of the rear of the frame (2), and a pair of semi-rollers (28) mounted at or adjacent the forward free end of each side member (4,6) of the frame (2) to be pivotal between an inoperat­ ive position extending fore and aft of the frame (2) and an operative position extending transversely across the open front of the frame, in which position a bale (54) within the frame (2) is rotatably supported by the rear roller (26) and the front semi-rollers (28). During this rotation of the bale (54), the bale (54) is wrapped in stretchable film material by a wrapping mechanism (38) on the machine, on completion of which wrapping the semi-­ rollers (28) are raised relative to the frame (12) to tip the wrapped bale (54) rearwardly of the machine over the rear roller (26) and onto the ground.

Description: This invention relates to machines for wrapping bales, more particularly so-called big round bales, in a stretch/cling film to prevent the ingress of air to the hay and thereby to improve the quality of the silage. It is now conventional practice to utilise baling machines to produce big round bales of hay, typically of the order of 1.2 to 1.8 metres in diameter and 1.2 metres in length, and to wrap the bales so formed in a stretch/cling film of plastic for storage purposes. Various mechanisms are known for wrapping the film around the bales in which the bales are wrapped as an entirely separate operation from the baling procedure, either by picking the bales up in the field in which they have previously been deposited by the baler, wrapping them and then leaving them in the field or by wrapping the bales at a predetermined site, typically a stack yard, to which the bales have previously been transported. However, the quality of the silage is, to a large extent, governed by how quickly air is excluded from the baled hay - clearly transportation to a stack yard or the like prior to wrapping enables the air to get to the hay and reduces the quality of the silage. Wrapping in the field is therefore to be preferred. However most existing mechanisms treat the wrapping operation as an entirely separate stage from the baling operation, and there is inevitably a delay between the steps of producing the bale and the wrapping thereof, interposed between which are the steps of lifting the bale from the ground prior to wrapping and returning the wrapped bale onto the ground after wrapping. This overall operation, as well as being time-consuming, requires the presence of manual labour and involves substantial handling of the bale in a manner which can damage the bale and/or the film applied thereto. It has been proposed, for example in United Kingdom specification no. 2159489, to provide a bale wrapping machine capable of wrapping a bale soon after it is discharged from the baler. However, this machine suffers from certain disadvantages, particularly in that, although it incorporates roller means for rotating the bale while it is being wrapped in film material, it requires the provision of a separate mechanism to lift the bale from the ground and onto the roller means. Furthermore, the bale, once located on the roller means, must be rotated about two mutually perpendicular axes simultaneously during the wrapping procedure. It would be desirable to be able to provide a bale wrapping machine of simpler, more compact construction in which the bale is more readily located thereon in a position to be wrapped. According to the present invention, there is provided a bale wrapping machine carrying a wheeled frame on which are mounted spaced-apart first and second roller means which can support and rotate a cylindrical bale on the frame, and a wrapping mechanism operable to wrap a rotating bale in stretchable film material, the second roller means being movable upwardly whereby the wrapped bale is tipped from the machine, characterised in that the wheeled frame is open-fronted and is adapted to be located about the bale to be wrapped, the first roller means comprising one or more rollers extending transversely of said frame at or adjacent the rear thereof, and the second roller means comprising a pair of semi-rollers one mounted at each side of the frame to be pivotal between an inoperative position extending substantially fore and aft of the frame and an operative position extending transversely of the frame at or adjacent the open front end thereof, the arrangement being such that, with the semi-rollers in their inoperative positions, the frame is located about the bale with the or each rear roller engaging a first region of the circumference of the bale, the semi-rollers then being moved to their operative positions to engage a further region of the circumference of the bale and whereby the bale is supported on, for rotation by, the rear roller or rollers and the front semi-rollers, the semi-rollers, on completion of the wrapping operation, being movable upwardly from their operative positions to displaced positions whereby the wrapped bale is tipped from the machine rearwardly over the or each rear roller. It will be appreciated that such a machine enables a bale to be wrapped entirely automatically, the machine conveniently being hitched to the rear of a baler whereby it is located about a bale as soon as it emerges from the baler, the movement of the baler and appropriate actuation of the second roller means loading the bale onto the machine for subsequent wrapping. During this wrapping procedure, the bale is rotated about a substantially horizontal axis only whereby the machines can, without modification, wrap bales of uneven shape or density whilst traversing ground of a steep gradient. Clearly such an arrangement minimises the time during which the bale is subjected to the atmosphere and therefore ensures high quality silage. Some only of the rear roller or rollers and the semi-rollers may be driven, although in a preferred embodiment all the rollers are driven, the external surfaces of said rollers conveniently being configured to improve frictional contact with the bale. Preferably the machine comprises an open-fronted sub-frame mounted in the wheeled frame, the semi-rollers being mounted at or adjacent the free ends of the side members of the sub-frame to be pivotal between their inoperative positions and their operative positions by means of associated hydraulic rams reacting between said side members of the sub-flame and the semi-rollers. Conveniently the sub-frame is mounted in the wheeled frame to be pivotal relative to the wheeled frame about an axis parallel with and closely adjacent the rear transverse member of the sub-frame, one or more hydraulic rams reacting between the wheeled frame and the sub-frame to effect said pivoting movement of the sub-frame and whereby the semi-rollers are raised from their operative positions to their displaced positions. Preferably one side member of the wheeled frame extends forwardly beyond the open front of the frame to comprise a drawbar to enable attachment of the machine to a baler or like towing vehicle. By way of example only an embodiment of the invention will now be described in greater detail with reference to the accompanying drawings of which: Figs. 1 and 2 are a plan view and a side view respectively of a machine according to the invention with the semi-rollers in their inoperative positions; Figs. 3 and 4 are a plan view and a side view respectively of the machine of Fig. 1 with the semi-rollers partially pivoted towards their operative positions; Figs. 5 and 6 are a plan view and a side view respectively of the machine of Fig. 1 with the semi-rollers in their operative positions, and Figs. 7 and 8 are a plan view and a side view respectively of the machine of Fig. 1 with the semi-rollers in their displaced positions. Referring to the drawings, the illustrated bale wrapping machine comprises a main frame 2 including opposed side members 4,6 and a rear member 8 defining an open front to the frame 2. The frame 2 is mounted on a pair of rear wheels 10 and the side member 4 is extended forwardly of the frame 2 to define a drawbar 12 by which the frame 2 can be attached to a towing vehicle such as a baler (not shown). Mounted within the main frame 2 is a sub-frame indicated generally at 14 and including a pair of opposed side members 16,18 and a rear member 20 defining an open front to the sub-frame 14. More particularly the sub-frame 14 is mounted on a pair of support members 22 secured to and projecting forwardly from the rear member 8 of the main frame 2, the sub-frame being pivotal about a horizontal axis P-P extending parallel with and just in front of the rear member 20 thereof by means of a hydraulic ram 24 reacting between the main frame 2 and the sub-frame 14 through a pivot shaft as will be described in more detail below. A roller 26 extends between the side members 16,18 of the sub-frame 14 adjacent the rear member 20 thereof, the axis of said roller 26 coinciding with the horizontal pivot axis P-P of the sub-frame 14, and the roller 26 being driven by a hydraulic motor (not shown). The external surface of the roller 26 is provided with longitudinal projections thereon to improve contact with a bale as will be detailed below. A pair of semi-rollers 28 are pivotally mounted one on the free-end of each of the side members 16,18 of the sub-frame 14, a pair of hydraulic rams 30 reacting between the side members 16,18 and the semi-rollers 28 and being operable to pivot the semi-rollers 28 about vertical axes between inoperative positions extending fore and aft of the sub-frame 14 as seen in Figs. 1 and 2 and operative positions extending transversely of the sub-frame 14 as seen in Figs. 5 and 6. More particularly, each semi-roller 28 is carried on a bracket 32 pivotally mounted at 34 on the free end of the associated side member 16,18, extension of the rams 30 pivoting the brackets 32 together with the semi-rollers 28 carried thereby, about said pivots 34. As with the roller 26, the semi-rollers 28 are provided with longitudinal projections on the external surfaces thereof and are driven by said hydraulic motor (not shown), said semi-rollers 28, in the operative positions thereof, extending substantially across the full width of the front open end of the sub-frame and at substantially the same level as the roller 26 above the ground. A pair of freely rotatable, upwardly projecting rollers 36 are located one intermediate the length of each side member 16,18 of the sub-frame to act as end restraints for a bale carried in the sub-frame as will become apparent from the following description, while a wrapping mechanism indicated generally at 38 is mounted on the main frame 2. The wrapping mechanism 38 comprises an upstanding support member 40 having an upper horizontal arm 42 carrying a rotatable wrap arm 44. More particularly, the wrap arm comprises a horizontal portion 46 pivotally mounted at 48 to the arm 42 of the support member 40, and a vertical portion 50 carrying a reel of film 52 and a dispensing mechanism therefor. The wrap arm 44 and reel 52 are rotatable about a vertical axis through the pivot 48 as indicated by the arrow 'A' in Fig. 5 by means of a hydraulic motor (not shown). The described machine is used to wrap a big round bale in stretchable film material as follows. The machine is hitched to the rear of a baler by means of the drawbar 12 and is set in its bale-receiving condition as shown in Figs. 1 and 2 with the sub-frame 14 substantially horizontal and with the semi-rollers 28 in their inoperative positions extending fore and aft of the machine along the direction of movement 'M' of the baler. A big round bale 54 is deposited by the baler in front of the bale wrapping machine as seen in Figs. 1 and 2, continued movement of the baler drawing the sub-frame 14 around the bale 54 until the roller 26 engages said bale 54. At this stage, the hydraulic rams 30 are actuated to pivot the semi-rollers 28 as seen in Figs. 3 and 4 towards their operative positions, said semi-rollers 28 engaging under the bale 54 whereby said semi-rollers 28, in conjunction with the rear roller 26, raise the bale 54 upwardly and rearwardly of the machine as indicated by arrow 'B' in Fig. 4 into the position shown in Figs. 6 and 7 in which it is supported above the ground by said roller 26 and semi-rollers 28. The roller 26 and the semi-rollers 28 are all driven in an anti-clockwise direction as viewed in Fig. 6 whereby the bale 54 supported thereon is rotated in a clockwise direction as indicated by arrow 'C' in Fig. 6, the rollers 36 engaging the ends of the bale 54 and serving to maintain the bale 54 centrally of the machine. As the bale 54 is being rotated about a horizontal axis on the machine, the wrapping mechanism 38 is actuated whereby the reel of film is rotated around the bale about a vertical axis through the pivot 48 and whereby the bale 54 is wrapped in relatively conventional manner in a stretchable film of plastics material. The speed of rotation of the wrap arm 44 and the reel 52 carried thereby is correlated with the speed of rotation of the bale 54 to ensure that the bale is totally encased in overlapping extents of the plastics film. Once the bale 54 has been completely wrapped, the film is severed and the hydraulic ram 24 is activated to pivot the sub-frame 14 in an anti-clockwise direction as viewed in Fig. 8 about the axis P-P and as indicated by the arrow D. The semi-rollers 28 are raised by the sub-frame 14 to the displaced positions shown in Fig. 8 while the rear roller 26 remains undisplaced, the wrapped bale 54 thus being tipped off the sub-frame 14 to roll under gravity from the machine and onto the ground behind the machine as indicated by arrow 'E' in Fig. 8. Once the bale 54 has been ejected from the machine, the hydraulic circuitry thereof is actuated to return the components of the machine back to the configuration of Figs. 1 and 2 ready to receive another bale from the baler. Thus it will be appreciated that the described machine enables a bale to be collected, wrapped and ejected entirely automatically and without the necessity for any supplementary handling or manual assistance. Although preferably being attached to the rear of a baler whereby the bales are wrapped immediately on emergence from the baler, the machine of the invention may be towed by any suitable prime mover, such as a tractor. Further, the bale can be wrapped on the move, there being no need to stop the prime mover before or during the wrapping operation - the bale is merely moved forwards on engagement by the roller 26 until it is lifted off the ground by the semi-rollers 28. The precise construction of the machine may vary from that described and illustrated without departing from the scope of the invention. Some only of the roller 26 and semi-rollers 28 may be driven, while the roller 26 may comprise a plurality of co-axial sub-rollers rather than the axially continuous roller shown. Conveniently separate hydraulic motors are provided one for driving the roller 26 and the semi-rollers 28 and one for driving the wrapping mechanism, although said motors are contained in the same hydraulic circuit and the speeds thereof can be adjusted to effect a desired overlap of film. The provision of a side-mounted drawbar 12 enables the machine to be manoeuvred about a bale by the towing vehicle without difficulty. The roller 26 and the semi-rollers 28 may be fabricated with the longitudinal external shapings integrally formed therewith, or may comprise cylindrical members to the external surfaces of which are attached axial slats or the like. Other modifications and variations from the described and illustrated arrangement will be apparent to those skilled in the art.

Claims: A bale wrapping machine carrying a wheeled frame (2) on which are mounted spaced-apart first and second roller means (26,28) which can support and rotate a cylindrical bale (54) on the frame (2), and a wrapping mechanism (38) operable to wrap a rotating bale (54) in stretchable film material (52), the second roller means being movable upwardly whereby the wrapped bale (54) is tipped from the machine, characterised in that the wheeled frame (2) is open-fronted and is adapted to be located about the bale (54) to be wrapped, the first roller means comprising one or more rollers (26) extending transversely of said frame (2) at or adjacent the rear thereof, and the second roller means comprising a pair of semi-rollers (28) one mounted at each side of the frame (2) to be pivotal between an inoperative position extending substantially fore and aft of the frame (2) and an operative position extending transversely of the frame (2) at or adjacent the open front end thereof, the arrangement being such that, with the semi-rollers (28) in their inoperative positions, the frame (2) is located about the bale (54) with the or each rear roller (26) engaging a first region of the circumference of the bale (54), the semi-rollers (28) then being moved to their operative positions to engage a further region of the circumference of the bale (54) and whereby the bale (54) is supported on, for rotation by, the rear roller or rollers (26) and the front semi-rollers (28), the semi-rollers (28), on completion of the wrapping operation, being movable upwardly from their operative positions to displaced positions whereby the wrapped bale (54) is tipped from the machine rearwardly over the or each rear roller (26). A machine as claimed in claim 1 in which all of the or each rear roller (26) and the semi-rollers (28) are driven. A machine as claimed in claim 1 or claim 2 in which the external surfaces of the or each rear roller (26) and of the semi-rollers (28) are configured to improve frictional contact with the bale (54). A machine as claimed in any of claims 1 to 3 and comprising an open-fronted sub-frame (14) mounted in the wheeled frame (2), the semi-rollers (28) being mounted at or adjacent the free ends of the side members (16,18) of the sub-frame to be pivotal between their inoperative positions and their operative postions by means of associated hydraulic rams (30) reacting between said side members (16,18) of the sub-frame (14) and the semi-rollers (28). A machine as claimed in claim 4 in which the subframe (14) is mounted in the wheeled frame (2) to be pivotal relative to the wheeled frame (2) about an axis (P-P) parallel with and closely adjacent the rear transverse member (20) of the sub-frame (14), one or more hydraulic rams (24) reacting between the wheeled frame (2) and the sub-frame (14) to effect said pivoting movement of the sub-frame (14) and whereby the semi-rollers (28) are raised from their operative positions to their displaced positions. A machine as claimed in any one of claims 1 to 5 in which one side member (4) of the wheeled frame (2) extends forwardly beyond the open front of the frame (2) to comprise a drawbar (12) to enable attachment of the machine to a baler or like towing vehicle.

Inventors: WALTON, JOHN DOWSON
Applicants: WALTON, JOHN DOWSON
Application year: 1989
Main classification: A01F15
IPC codes: A01F15