IES20020925A2 - Bale wrapping machine - Google Patents

Abstract

A bale wrapping machine (10) for wrapping bales of material (5), in particular large rectangular, square or round bales of material, with a strip of wrapping material characterised in that it comprises a means for rotating the bale about a substantially horizontal axis (60), and means (9) for supplying a strip of wrapping material to the bale (5) as the bale is turned about the horizonal axis (60). The means for rotating the bale comprises two roller units, which are disposed in predetermined spaced parallel relationship to each other and which are adapted to engage a bale for wrapping. At least one (6) of the roller units comprises two parallel rotatable rollers (11,12) spaced apart, and the roller unit (6), including said two rollers, is mounted for rotation (i.e. rocking) about a transverse axis (23). A conveyor belt (50) is fitted for travel about the said two rollers, and preferably extends for substantially the full width of the rollers. <Figure 1>

Description

Field of the Invention The invention relates to a wrapping machine, in particular to a bale wrapping machine for use in pre-stretching plastics wrapping film. The device is particularly suitable for use in pre-stretching webs of plastics film used in agricultural bale wrapping machines for wrapping bales of fodder. The invention is particularly concerned with wrapping machines for wrapping bales of agricultural silage, grain, hay, straw, maize, beet pulp, beet tops, and the like (hereinafter referred to as “fodder”) with a plastics film, which preferably is air tight and water tight. The device of the invention may also be used in conjunction with machines for compacting and wrapping general farm and agricultural waste products, such as waste plastics and the like, and for wrapping other loose materials and objects such as comminuted peat moss, saw dust, wood shavings, wood chippings, brewery waste, bricks, blocks, cartons and the like.

Background to the Invention It has become conventional practice in agriculture to form harvested fodder into cylindrical-shaped bales, and square or rectangular bales, which are then wrapped in a plastics film. This is particularly suitable method of manufacturing silage because the silage is kept air-tight within the wrapped bale which, typically, is wrapped with up to six plies of plastics film. The cylindrically shaped bales are commonly called “big round bales”. Machines for wrapping big round bales with a plastics film are described, for example, in GB 2191984 A, GB 2228246A and EP 0208034A (GB 2159489B).

Bale wrapping machines of the kind described comprise a wheeled chassis which / may be towed by a tractor. The chassis carries a tipping platform which, in turn, \ supports a turntable. The turntable is rotatable about a vertical axis. The turntable carries a pair of spaced apart each of which rotates about a horizontal axis. An endless IE 0 2 0 9 2 5 bet is stretched between the rollers and rotates with the rollers, In order to wrap a large round bale of fodder material with plastics film, the round bale is lifted onto the turntable by means of lifting arms. The bale rests on the endless belt. The free end of a roll of plastics film is attached to the bale and the turntable is then rotated about a generally vertical axis to cause the sheet of film to be wrapped around the bale, However if no movement of the bale about its longitudinal axis were to occur the bale would merely be wrapped with a single band having the thickness of the width of the plastics film. However, on each rotation of the turntable the endless belt is caused to move for a predetermined distance which, in turn, causes the bale to roll about its surface, i.e. about a horizontal axis. This rolling of the bale on the belt allows a new area of bale to be wrapped by the film on each rotation of the turntable, thus eventually achieving a complete covering of the bale with a substantial degree of overlap of the plastics film.

In the bale-wrapping machines described above the bale to be wrapped is mounted on a turntable which rotates about a vertical axis, and the dispenser for the roll of plastics film is fixed, It is the rotation of the bale about the vertical axis which causes the film to be unrolled from the dispenser. However, it is also known from the prior art, for example in EP-B-0110110, DE 3642513A, and GB 2193683A, for the bale to be mounted on rollers which rotate the bale only about the horizontal axis. In this arrangement there is provided a rotary support arm for the film dispenser which rotates the film dispenser, about a vertical axis, around the bale, while the bale is being turned about a horizontal axis.

Many farmers now use bale machines which form the fodder into large bales of a substantially rectangular or square shape. Such machines include Ford New Holland DI000, Hesston 4600, Hesston 4700, Welger Delta 4000, Mengle SB 8280, Claas Quadrant, Deutz Fahr G.P. 3.612. The bales produced by these machines are commonly referred to as “big square bales”. These bales may, in fact, have a cross-section which is either square or rectangular. These bales present a problem because they cannot adequately be wrapped with film using conventional round bale wrapping machines.

IE 0 2 0 9 2 5 A known bale wrapping machine which can be successfully used for wrapping big square bales of fodder is that disclosed in EP 0 539 549 BI (Idough Investment Company). This discloses a wrapping machine for wrapping large rectangular or square bale of fodder with a strip of wrapping material, comprising a support for the bale, conveying means to turn the bale about a horizontal axis, and means for continuously supplying a strip of wrapping material to the bale as the bale is turned through said axis to wrap the wrapping material around the bale. The conveying means comprises a slack endless conveyor belt suspended above the support and includes drive means for the belt such that a first portion of the belt travels upwardly in an upwardly inclined path at one end of the support while a second portion of the belt travels downwardly in a downwardly inclined path at an opposite end of the support. The endless conveyor belt has a substantial sag in the conveyor belt which defines a cradle in the belt to receive the bale and is adapted to assume a substantially u-shape or v-shape when a bale is placed on the belt, the sag in the belt being such that there is contact between the belt and adjoining sides of the bale during rotation of the bale which maintains control of the rotational movement of the bale as the bale is turned about a horizontal axis of the bale.

Another bale wrapping machine which is suitable for use in wrapping both square and round bales is that which is commonly referred to a “Rocking Roller” bale wrapper and is described, for example in EP 0 543 792 (Tellefsdal A/S). This discloses a bale wrapping machine for wrapping parallelepipedic shape bales, such as square bales with a plastics wrapping material. The wrapping machine comprises means for rotating the bale around a substantially horizontal axis, characterised in that the means for rotating the bale comprises two roller units, each of which comprises at least two rollers, which are disposed in a pre-determined spaced parallel relationship to each other and which are able to engage the bale, and drive means for rotating the rollers, each roller unit being pivotably biased about and mounted on the axis of the drive means, two such spaced apart roller units which in operation being able to turn a parallelepipedic bale through 360° around the horizontal axis.

The rocking roller type bale wrapping machine as described in EP 5 543 792 (Tellefsdal A/S) has a number of advantages. It is compact and efficient in use, may be ®®2θ925 mounted on the front, rear or forklift/teleporter mounting on a tractor and so is very versatile in use. It is capable of wrapping square and round bales of grass silage.

However, one disadvantage which has become apparent with conventional rocking roller type bale wrapping machines is that problems are encountered when wrapping large and heavy bales of fodder, refuse and other materials. The rollers of the rocking roller type bale wrapping machine usually are provided with a ribbed profile which is intended to grip the square bale as it is rotated about a horizontal axis by the machine. It has been found that when the bales are very heavy, e.g. of the order of 1 ton in weight, damage is caused to the wrapping film, which can be heavily abraded or torn. This is partly caused by the fact that all of the rollers are driven. This damage usually occurs when the corner of the bale comes into contact with a roller when raising the bale upwardly along an inclined path. Also, the small area of contact between the driven rollers and the bale also contribute to the problem of slippage between the bale and the rollers.

Ob ject of the Invention It is an object of the invention to provide an improved bale wrapping machine of the rocking roller type which is capable of handling very heavy square bales with less risk of slippage or of damage to the bale wrapping material. It is also an object of the invention to simplify the drive arrangement for such bale wrapping machines.

Summary of the Invention The invention relates to a bale wrapping machine suitable for wrapping a large rectangular, square or round bale of material with a strip of wrapping material, comprising means for rotating the bale about a substantially horizontal axis, and means for supplying a strip of wrapping material to the bale as the bale is turned about the horizontal axis, wherein the means for rotating the bale comprises two roller units, which are disposed in predetermined spaced parallel relationship to each other and which are adapted to engage a bale for wrapping, wherein at least one of the roller units «Ε 02 092 5 comprises two parallel rotatable rollers spaced apart, and the roller unit, including said two rollers, is mounted for rotation (i.e. rocking) about a transverse axis, and wherein a conveyor belt is fitted for travel about the said two rollers. The conveyor belt extends for substantially the full width of the rollers.

In one embodiment each of the two roller units comprises two rollers, and a conveyor belt is fitted about each pair of rollers.

Suitably, one of the rollers in each roller unit is a driven roller and the other roller is an idle roller.

In a second embodiment one of the roller units is a rockable unit comprising two parallel spaced rollers with a conveyor belt fitted for travel about the two rollers, and the other roller unit comprises a single roller.

The invention also relates to a wrapping machine for wrapping a bale of material of a parallelepipedic form, wherein plastics sheeting is wrapped in layers or overlapping around said bale, said machine comprising means for rotating the bale around a substantially horizontal axis, wherein the said means for rotating the bale comprises two roller units, each of which comprises at least two rollers, which are disposed in a predetermined spaced parallel relationship to each other and which are able to engage the bale, and drive means for rotating at least one of the rollers, each roller unit being pivotably biased about and mounted on the axis of the drive means, two such spaced apart roller units when in operation being able to turn a parallelepipedic bale through 360a around said substantially horizontal axis, characterised in that an endless conveyor belt is fitted for travel about the two rollers in each of the roller units. Preferably, the endless belt has a width which is substantially the width of the rollers. Preferably, one roller in each roller unit is a driven roller and the other roller is an idle roller. The invention may also be supplied as an attachment for a wrapping machine.

IE 0 2 0 9 2 5 Brief Description of the Drawings One embodiment of the invention is hereinafter described with reference to the accompanying drawings wherein: Figure 1 is a perspective view of a rocking roller type bale wrapping machine in accordance with one embodiment of the invention; Figure 2 is a schematic front view of the machine as shown in Figure 1; Figure 3 is a schematic front view of a bale wrapping machine in accordance with a second embodiment of the invention; Figure 4 is a perspective view of components of the machine of Figure 1 and 3; Figure 5 is a schematic diagram showing the sequence of operation of the wrapping machine of Figure 1 in rotating a bale 5; and Figure 6 is a similar view showing the sequence of operation of the machine of Figure 3.

Detailed Description of the Drawings Referring firstly to Figures 1 and 2 these show a rocking roller type bale wrapping machine 10 in accordance with a first embodiment of the invention. The machine comprises two spaced apart roller units 4 and 6 which support a square bale 5 of fodder which is shown in the drawings in broken line, and which are adapted to rotate the bale 5 about its substantially horizontal axis 60. A rotary arm 3 is adapted to support a film dispensing device 9 which is rotated, in a circular path, about the square bale 5 to wrap it in plastics film, in well known manner, as the bale 5 is turned about a substantially horizontal axis by the roller units 4, 6.

The roller units 4, 6 are spaced apart a distance which is adapted to the longitudinal or lateral dimensions of the bale 5.

The roller unit 4 comprises a driven roller 1 and an idle roller 2. Likewise, the roller unit 6 comprises a driven roller 11 and an idle roller 12. The driven rollers 1, 11 are driven to rotate by drive belts 31,35 respectively as described more fully below.

IE 0 2 0 9 2 5 Alternatively, drive may be by means of a belt drive, direct cogwheel transmission or friction transmission.

At the rear of the roller units 4, 6 two support rollers 7 are mounted, against which the bale 5 rests.

Figure 2 illustrates schematically the wrapping machine 10 viewed from the front where the bale 5 has started its rotational movement. As can be seen from Figure 2, the bale 5 rests, in this phase, on all of the rollers 1, 2,11 and 12.

As shown in Figure 2, the rollers 1 and 2 are mounted for rotation on suitable bearings in a substantially L-shaped frame 21. The frame is mounted on an elongate square steel box section 26. The roller unit 4, comprising the frame 21 and the rollers 1, 2, can pivot (i.e. rock) about an axis 24. The axis 24 is located substantially mid-way of the L-shaped frame 21, and corresponds to the drive axis.

Likewise, the roller unit 6 comprises an L-shaped frame 22 mounted on an elongate steel box section 28. The frame 22 together with the rollers 11,12 which are rotatably mounted on the frame 22, in suitable bearings, is free to pivot about the axis 23, which also corresponds to the drive axis.

The roller unit 4 is powered by a drive shaft which extends axially within the box section 26 and terminates in a sprocket 30 which is connected by a belt 31 to a sprocket 32 on the end of the driven roller 1. Likewise, in roller unit 6 a drive shaft terminates in sprocket 33 which drives a sprocket 35 on the end of the driven roller 11 by means of a drive belt 34.

This pivotal or rotational movement of the frames 21, 22 goes beyond or is restricted to turning through a certain predetermined angle. The roller units 4,6 are also biased in the sense that the rotational movement around the axes 23,24, respectively, takes place against a certain pretension, so that the roller unit 6, without the load of a bale 5, will be forced around said axis 23 in an anti-clockwise direction, and in a IE 0 2 0 9 2 5 clockwise direction in the left-hand roller unit 4 in figure 2. The roller units 4, 6 can also be moved towards and away from one another horizontally, e.g. by a hydraulic ram, in order to be able to handle bales of different sizes, and to squeeze the roller units 4, 6 against the bale 5. Each roller unit 4, 6 may pivot (or rock) about the axis from a position in which the two rollers are disposed horizontally, to a position in which they are disposed vertically, one above the other. Thus, the range of pivotal movement is about 90s.

An endless conveyor belt 40 is fitted about the rollers 1 and 2. The belt 40 extends transversely for the full width of the rollers 1 and 2. The endless belt 40 is mounted for rotary movement about the rollers 1, 2.

The rollers rotate in the direction of the arrows shown in the drawings.

A similar belt 50 is mounted for rotary movement about the rollers 11,12.

The belts 40, 50 may be made from a suitable rubberised fabric and may have a smooth surface. Alternatively, the surface of the belts 40, 50 may be provided with cleats, ribs or the like to improve their frictional properties.

One embodiment of the conveyor belt 40, 50 is shown in Figure 4. Figure 4 also shows the driven rollers 1,11 and an idle roller 2,12. Preferably, a grip-face 38 is applied to the surface of the driven roller 1,11. The grip-face may be a raised ridge or knurling arranged in a spiral about the roller. The grip face has been found to prevent slippage between the roller 1,11 and the belt 40, 50, and provides a positive drive. The spiral pattern of the grip face 38 also aids belt tracking and alignment. Suitably, the idle rollers 2, 12 have a smooth face, which aids constant alignment of the conveyor belt 40, 50.

We have found that the use of a full-width conveyor belt on the rollers results in a number of significant advantages over the prior rocking roller bale wrapper as described in EP 0 543 793. For example the conveyor belts 40,50 guide the leading IE 0 2 0 9 2 5 lateral edges of the bale 5 between the rollers of the roller units 4, 6, and provide a more even drive over a large surface area. The conveyor belts 40,50 also support heavy bales over the same increased surface area and prevent jamming of the bale 5 or damage to the bale wrapping.

In the embodiment of Figures 1 and 2 the number of drive components and drive requirements are reduced as compared to the prior art rocking roller. In the embodiment of the invention only one driven roller 1,11 is required for each of the roller units 4, 6. The second driven roller of the prior art arrangement has been replaced with a smooth idle roller, which aids constant alignment of the conveyor belts 40,50. The spiral pattern which forms the grip face 38 on the driven rollers 1,11 prevent slippage between the roller and the belt and provides a positive drive. The grip face 38 also aids belt tracking alignment. The use of full width conveyor belts 40,50 also provide a more positive drive, especially when wrapping uneven or badly tied bales 5. The full width belts 40, 50 aid in expelling air from the compacted bale 5 and ensure tighter wrap of plastic wrapping on the bale 5.

A second embodiment of a wrapping machine in accordance with the invention is now described with reference to Figure 3. In this embodiment the right-hand roller unit 6 is constructed and operates substantially as described above with reference to Figure 2.

However, in this embodiment the left-hand roller unit 4 is replaced by a roller unit 20. The roller unit 20 comprises a single roller 42 which is mounted for rotation in bearings in brackets 43. The roller 42 rotates in the direction of the arrow shown in Figure 3. The brackets 43 do not rock or pivot unlike the frame 22. However, the roller unit 20 is moveable horizontally by means of a hydraulic ram. The roller 42 is a driven roller and is driven by a chain drive, or like means, (not shown).

Because of the full width of the conveyor belt 50 on the rocking roller unit 6, it has been found with this embodiment that there is no loss in surface driven/supported area. Indeed, there is an increase in these parameters over the prior art rocking roller 12 '02 17:14 ]·ΛΧ 00 1 IE 0 2 0 9 2 5 machine. However, this embodiment is much more simple and cost effective than the prior art rocking roller machine.

Figure 5 is a schematic diagram showing the sequence of operation of the wrapping machine of Figures 1 and 2 in rotating the bale 5. It also illustrates how the roller units 2, 6 rock during rotation of the bale 5.

Figure 6 is a similar diagram showing the operation of the embodiment of Figure 3.

It would be appreciated that it would be possible to replace the full width belt 40, with a plurality of parallel strip belts. While these may assist in supporting the heavy bale they are not as advantageous as the full width belt because the belt tends to sag in the gaps between the strip belts.

The words “comprises/comprising” and the words “having/including” when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

From the foregoing, it will be apparent that numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concept of the present invention. It will be appreciated that the present disclosure is intended to set forth the exemplifications of the invention which are not intended to limit the invention to the specific embodiments illustrated. The disclosure is intended to cover by the appended claims all such modifications as fall within the scope of the claims.

Where technical features mentioned in any claim are followed by reference signs, these reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the scope of each element identified by way of example by such reference signs. ΙΕ 0 2 0 9 2 5 d.3-12 '02 17:16 Ι’ΛΧ ιι It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.

Claims (6)

1. A bale wrapping machine for wrapping bales of material, in particular large rectangular, square or round bales of material, with a strip of wrapping material characterised in that it comprises a means for rotating the bale about a substantially horizontal axis, and means for supplying a strip of wrapping material to the bale as the bale is turned about the horizontal axis, wherein the means for rotating the bale comprises two roller units, which are disposed in predetermined spaced parallel relationship to each other and which are adapted to engage a bale for wrapping, wherein at least one of the roller units comprises two parallel rotatable rollers spaced apart, and the roller unit, including said two rollers, is mounted for rotation (i.e. rocking) about a transverse axis, and wherein a conveyor belt is fitted for travel about the said two rollers.

2. A bale wrapping machine for wrapping a bale of material of a parallelepipedic form, wherein plastics sheeting is wrapped in layers or overlapping around said bale, said machine comprising means for rotating the bale around a substantially horizontal axis, wherein the said means for rotating the bale comprises two roller units, each of which comprises at least two rollers, which are disposed in a pre-determined spaced parallel relationship to each other and which are able to engage the bale, and drive means for rotating at least one of the rollers, each roller unit being pivotably biased about and mounted on the axis of the drive means, two such spaced apart roller units when in operation being able to turn a parallelepipedic bale through 360° around said substantially horizontal axis, characterised in that an endless conveyor belt is fitted for travel about the two rollers in each of the roller units.

3. A bale wrapping machine as claimed in Claim 1 or Claim 2 wherein each of the two roller units comprises two rollers, and a conveyor belt is fitted about each pair of rollers, said conveyor belt extending for substantially the full width of the rollers.

4. A bale wrapping machine as claimed in Claim 1 wherein one of the roller units is a rockable unit comprising two parallel spaced rollers with a conveyor belt fitted for IE 0 2 0 9 2 5 travel about the two rollers, said conveyor belt extending for substantially the full width of the rollers, and the other roller unit comprises a single roller.

5. A bale wrapping machine as claimed in any previous claim wherein each roller unit 5 comprises one driven roller, and the or each other roller in each roller unit is an idle roller.

6. A bale wrapping machine substantially as hereinbefore described with reference to Figures 1 to 6 of the accompanying drawings.