IES65206B2 - A bale wrapper - Google Patents

Abstract

A bale wrapper (10) comprises a turntable (11) mounted on a base frame (12). The turntable has spaced apart roller means (13) and drive means for rotating the turntable relative to the base frame and for rotating the roller means. The base frame is connected to a support frame (14) on which a roll of sheeting (61) is mounted. The turntable is adapted so that, in use, a bale (60) mounted on said turntable is rotated by the drive means to draw sheeting from the roll and wrap the bale in sheeting. The bale wrapper includes grasping means (64) disposed between the turntable and the roll of sheeting to engage the sheeting after the bale is wrapped.

Description

A Bale Wrapper The present invention relates to a bale wrapper.

According to the present invention there is provided a bale wrapper comprising a turntable mounted on a base frame, the turntable having spaced apart roller means, drive means for rotating the turntable relative to the base frame and for rotating the roller means, said base frame being connected to a support frame on which a roll of sheeting is mounted, said turntable being adapted so that, in use, a bale mounted on said turntable is rotated by the drive means to draw sheeting from the roll and wrap the bale in sheeting wherein the bale wrapper includes grasping means disposed between the turntable and the roll of sheeting to engage the sheeting after the bale is wrapped.

Preferably, said grasping means comprises an extendible ram cooperable with stopper means, said ram being movable from a retracted position, in which the sheeting passes between the ram and the stopper, to an extended position, in which the sheeting is grasped between the ram and the stopper.

Further preferably, one end of said ram is located within a cylinder, said end of the ram being adapted to divide said cylinder into two compartments, the first compartment being supplied with a fluid through a first valve and said second compartment communicating with a fluid accumulator through a second valve so that fluid is displaced from said second compartment when said piston is displaced within the cylinder on supply of fluid under pressure through said first valve, said first fluid supply further communicating through a non-return valve to said accumulator so that fluid pressure in the accumulator is maintained. 365206 Preferably, cutting means are associated with said grasping means to cut said sheet after the bale is wrapped.

More preferably, gathering means disposed between the turntable and the dispensing roll are provided to gather the sheeting after the bale is wrapped.

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side view of a bale wrapper according to the invention; Figure 2 is a perspective view of the support frame of the bale wrapper of Figure 1; Figure 3 is a detailed elevation view of a dispensing roll for the bale wrapper of Figure 1; Figure 4 is a plan view of the apparatus of Figure 3; Figure 5 is a cross-sectional view of a grasping mechanism for the bale wrapper of Figure 1; Figure 6 is a side view of the bale wrapper of Figure 1 with a bale being wrapped; Figure 7 is a side view of the bale wrapper of Figure 1 in a tipping position; and Figure 8 is a schematic view of the gathering apparatus of the bale wrapper of Figure 1; Referring now to the drawings wherein similar numerals have been used to indicate like parts, there is shown therein a bale wrapper generally indicated at 10 according to the invention. The bale wrapper 10 comprises a turntable 11 rotatably mounted on a base frame 12. A pair of parallel spaced apart rollers 13 are rotatably mounted on the turntable. The rollers are driven by a drive mechanism (not shown) located under the turntable. The base frame 12 is pivotally mounted on a post 15. The post 15 projects upwardly from a support frame 14 which extends horizontally under the turntable 11 and upwardly adjacent the side of the turntable 11.

The support frame 14, Figure 2, comprises a substantially rectangular member 18 which in use is disposed in a horizontal plane. A substantially U-shaped member 19 is attached by its ends 20 to one side 22 of the rectangular member 18 and projects perpendicularly from the rectangular member 18. The support frame 14 is in use attachable to a tractor via a conventional three point linkage 17, Figure 1.

A hydraulic tipping ram 16 is pivotably attached between the base frame 12 and the support frame 14 such that, as the ram 16 extends, the base frame 12 and hence the turntable 11 pivot about the post 15 away from the U-shaped member 19 to a tipping position, Figure 7.

Referring to Figure 2, a beam 24 extends from one side of the U-shaped member 19 parallel to the side 22. A substantially rectangular pillar 26 extends upwardly from the beam 24. A hollow substantially rectangular sleeve 28 is slidably mounted on the pillar 26 such that the pillar 26 is at least partially contained within the sleeve 28. A single acting hydraulic ram 30 is attached between the beam 24 and the sleeve 28 so that the ram 30 may move the sleeve 28 along the common axis of the sleeve 28 and the pillar 26.

An L-shaped gathering arm 32 comprises a crook 33 and a shaft 34. The crook 33 is disposed parallel to the beam 24. The distal end 35 of the shaft 34 is pivotably attached to one end of a rod 36. The distal end 45 of the rod 36 extends towards the beam 24 but is not connected thereto. The shaft 34 is pivotably mounted on the sleeve 28 at a point 37 adjacent the end 35. As the gathering arm 32 pivots the crook 33 moves towards or away from the beam 24 along a path A, Figure 1. A spring 38 is attached between the sleeve 28 and the shaft 34 of the gathering arm 32. The spring 38 is biassed such that in use it tends to pivot the gathering arm 32 upwards.

In use, the gathering arm 32 moves from an initial position in which the ram 30 is fully extended and the end 45 of the rod 36 is clear of the beam 24. When operated, the ram 30 is retracted so that the sleeve 28 and the gathering arm 32 move downwards. The end 45 of the rod 36 engages the beam 24 causing the crook 33 to pivot in a downward direction. The crook 33 is lowered approximately 400 mm by retracting the ram 30 and a further 300 mm as a result of pivoting about the point 37. This enables plastic sheeting to be gathered as is described below in greater detail.

At the opposite side of the rectangular member 18 to the gathering arm 32 there is provided a substantially U-shaped loading member 39 comprising two legs 40 and a crossbeam 41. One leg 40 lies adjacent a side 42 of the rectangular member 18 and is pivotably connected thereto. The loading member 39 is pivotable between a horizontal loading position and a vertical dispensing position.

A plastic sheeting stretching and dispensing apparatus 50 is attached to the sleeve 28 and is disposed between the sleeve 28 and the path A of the crook 33, Figure 1. The apparatus 50 comprises a frame 51 which carries a spindle 52 on which a roll of plastic sheet material 61 is mounted, Figure 3. The frame 51 also supports first and second rubber coated dispensing rollers 53, 54 respectively. The dispensing rollers 53, 54 are mounted for rotation in suitable bearings (not shown).The dispensing rollers 53, 54 are attached to respective gear wheels 55, 56 which are meshed together, the gear wheels being located in a housing 59. The roller 54 is of a greater diameter than the roller 53. As the plastic sheet material 61 is drawn outwards by a bale 60 being wrapped, the sheet 61 passes between the rollers 53, 54 as shown in Figure 4 and the friction between the sheet 61 and the rollers causes them to rotate at the same speed. However, because of the greater diameter of roller 54 compared with roller 53, the plastic sheet 61 is stretched slightly and this is desirable in wrapping bales.

Referring to Figure 6, a substantially U-shaped bar 62 spans one side of the turntable 11 in the direction of the axis of the rollers 13. A spring loaded rubber stopper 63 is mounted on top of one end of the bar 62. A cutting blade (not shown) is attached to the bar 62 and runs parallel to the stopper 63.

A grasping apparatus 64 comprises a single acting hydraulic ram 65 and a gas filled accumulator 66 fixed to the top of the bar 62. The grasping apparatus 64 is positioned so that the hydraulic ramrod 67 extends towards and in line with the stopper 63. Furthermore, the grasping apparatus 64 is positioned so that, at full extension, the ramrod 67 is able to displace the spring loaded stopper 63 by approximately 50 mm. The grasping apparatus is used to grasp plastic sheeting as is described below in greater detail.

Figure 5 shows a cross-sectional view of the grasping apparatus 64. The hydraulic ram 65 has a cylinder 68 with a rod end 69 and a feed end 70. The ramrod 67 is attached to a seal 73 within the cylinder 68. The gas filled accumulator 66 is connected to the rod end 69 of the cylinder 68 and an oil feed pipe 71 is connected to the feed end 70. The rod end 69 and the feed end 70 are connected externally of the cylinder 68 via a check valve 72. Oil is able to flow from the feed pipe 71 to the rod end 69 via the check valve but is unable to flow in the reverse direction. The accumulator 66 has a capacity of 0.1 litres and is pre-charged with Nitrogen gas at 40 BAR.

In use, oil is fed through the feed pipe 71 into the feed end 70. Oil pressure causes the seal 73 (and the ramrod 67) to move towards the rod end 69 of the cylinder 68 thereby extending the ram 65. Thus, oil which had filled the cylinder between the seal 73 and the rod end 69 is forced into the accumulator 66, compressing the nitrogen gas. The ram 65 will continue to extend until there is a pressure balance on either side of the seal 73. Oil which may be lost through wear or leakage from the rod end 69 of the cylinder 68 is automatically replenished from the feed pipe 71 via the check valve 72 so that the pressure balance and the desired rod extension are maintained.

To retract the rod 67, the oil flow through the feed pipe 71 is stopped. Hence, oil pressure in the feed end 70 of the cylinder is reduced and the nitrogen gas within the accumulator 66 expands. Thus, the oil which had been stored within the accumulator 66 is forced back into the rod end 69 of the cylinder 68 pushing the seal 73 back towards the feed end 70 and retracting the rod 67.

Referring to Figure 6, a bale 60 of silage is loaded onto the loading member 39 when in the loading position, Figure 2. The loading member then pivoted through approximately 90 degrees into the dispensing position where the bale 60 slides onto the rollers 13.

Diametrically opposed rollers 31 are provided on either side of the turntable 13 and serve to retain the bale 60 on the turntable.

Once the bale 60 is located on the rollers 13, the plastic sheeting 61 is manually tucked into the bale 60 to form a secure attachment. The bale 60 is then wrapped in the plastic sheeting 61 by rotating the bale 60 about a substantially vertical axis and a substantially horizontal axis by means of the turntable 11 and the rollers 13 respectively.

Referring now to Figures 6 and 7 the procedure for unloading the bale 60 will now be described. Once wrapping is completed, the turntable 11 is rotated until the grasping apparatus 64 faces the dispensing apparatus 50, Figure 7. The gathering arm 32 is then operated, as described above, so that the plastic sheeting 61 is gathered against the bar 62 adjacent the stopper 63.

The tipping ram 16 is then actuated so that the turntable 11 is pivoted away from the dispensing apparatus 50. The ram 65 of the grasping apparatus 64 is extended until the gathered plastic sheeting 61 is grasped between the ramrod 67 and the stopper 63. As the ram 65 continues to extend, the plastic sheeting is severed by the cutting blade (not shown) so that the bale 60 is free to slide off the rollers 13.

Figure 8 illustrates the configuration of a hydraulic system which ensures that the gathering operation is performed before the tipping operation. A relief valve 74 and a check valve 75 are incorporated into oil flow lines 76 to control the flow of oil. The configuration is such that the relief valve 74 can only deliver oil to the tipping ram 16 after the ram 30 has operated. Thus, the ram 30, used in the gathering operation, always operates before the tipping ram 16.

One advantage of the invention is that the end of the plastic sheeting 61 remains gathered and held by the grasping apparatus 64 even after a bale has been unloaded. Thus, attaching the sheeting 61 to subsequent bales is greatly facilitated.

Further advantages of the invention are that the bale wrapper is functional, simple and fast to operate; compact in appearance and design, and relatively inexpensive to produce.

Claims (5)

CLAIMS :

1. A bale wrapper comprising a turntable mounted on a base frame, the turntable having spaced apart roller means, drive means for rotating the turntable relative to the base frame and for rotating the roller means, said base frame being connected to a support frame on which a roll of sheeting is mounted, said turntable being adapted so that, in use, a bale mounted on said turntable is rotated by the drive means to draw sheeting from the roll and wrap the bale in sheeting wherein the bale wrapper includes grasping means disposed between the turntable and the roll of sheeting to engage the sheeting after the bale is wrapped.

2. A bale wrapper as claimed in claim 1, wherein a grasping means comprises a extendible ram cooperable with stopper means, said ram being movable from a retracted position, in which the sheeting passes between the ram and the stopper, to an extended position, in which the sheeting is grasped between the ram and the stopper.

3. A bale wrapper as claimed in claim 2, wherein one end of said ram is located within a cylinder, said end of the ram being adapted to divide said cylinder into two compartments, the first compartment being supplied with a fluid through a first valve and said second compartment communicating with a fluid accumulator through a second valve so that fluid is displaced from said second compartment when said piston is displaced within the cylinder on supply of fluid under pressure through said first valve, said first fluid supply further communicating through a non-return valve to said accumulator so that fluid pressure in the accumulator is maintained.

4. A bale wrapper as claimed in claim 1, 2 or 3, wherein cutting means are associated with said grasping means to cut said sheet after the bale is wrapped.

5. A bale wrapper as claimed in claims 1, 2, 3 or 4, wherein gathering means disposed between the turntable and the dispensing roll are provided to gather the sheeting after the bale is wrapped.