GB2200887A - Bale wrapper - Google Patents

Abstract

Bale-wrapping apparatus 10 for applying a band of plastics material 12 to a round bale 11 by simultaneous rotation of the bale about vertical and horizontal axes 13 and 14 comprises a base 15 supported by wheels 16, and a support frame 17 which is pivotally mounted on the base 15 via a pivot mounting 18 for raising and lowering by a ram 19. A pair of driven bale-supporting rollers 21 are mounted on a rotary platform 20 carried by the support frame, and slack belts 22 circulate around the rollers. Drive means for simultaneously rotating the platform 20 the rollers 21 includes a large ring or slew gear 24 having an upstanding housing 25 which extends upwardly into the platform 20 to which it is secured. Radial struts 26 are secured to the housing 25 and to the platform 20, and drive is transmitted from a motor M to the ring gear 24 by an input gear 27. The platform mounts a gear housing within housing 25 for rotation about a fixed gear carried on a stationary upstanding shaft 31 (Fig. 3) to rotate on gear 33 of an output shaft 34 and hence a chain and sprocket linkage 35, 36, 37 (Fig. 4) to at least one of the rollers 21 on rotation of the gear housing with the platform about the fixed gear. <IMAGE>

Description

BALE WRAPPER This invention relates to a bale wrapper for applying a continuous- wrapping strip around a bale in order to enclose the bale.

Farmers are using increasingly large round bales to store straw, hay and silage, but it is only fairly recently that consideration has been given to wrapping these round bales with a weatherproof cover for protection during storage. Prior to the use of weatherproof covers, bales have often been stored in stacks where they are completely exposed to weather conditions, and therefore undergo deterioration with time.

It is highly desirable to protect round and other bales against the weather, and particularly rain, since water penetration causes deterioration in the quality of the stored crop. However, to date, wrapping of round bales has been a largely manual operation, in which large black plastic bags, somewhat in the form of enlarged "dustbin bags" or bin liners, have been manually fitted over and then closed as tightly as possible around the bale. This is a time consuming and labour-intensive task, and it is a matter of practical experience that the bags do not always remain properly closed after prolonged exposure to adverse weather conditions, and particularly if they have not been tightly closed around the bale initially, or have become loosened by wind.

There has therefore developed a need to provide a means for automatically wrapping round bales in a way which reduces the manual labour content of the operation, and which also operates to provide a reliable enclosure of the bales within the applied wrapping.

According to the invention there is provided a balewrapping apparatus which comprises: a base; a support frame mounted on the base; a platform rotatably mounted on the support frame for rotation about an axis extending generally perpendicular to the general plane of the support frame; a pair of rollers mounted on the platform with their axes substantially parallel to each other and laterally spaced apart to form a bale-receiving arrangement onto which a round bale can be placed so as to be held captive on the platform and with its axis extending substantially parallel to the plane of the support frame; and drive means for rotating the platform about its axis of rotation with respect to the support frame, and for rotating the rollers simultaneously with the rotation of the platform in order to rotate the bale, when supported by the rollers; and, a dispenser mounted on the base and adapted to supply a band of wrapping material to wrap the bale, the band being attached to the bale and being applied as a wrapping around the bale which progressively covers the bale as the platform is rotated about its axis and the bale is rotated about its axis by the rollers; in which the drive means comprises: a ring gear secured to the underside of the platform for rotation therewith; an input gear coupled with the ring gear; a gearbox mounted on or in the upper side of the platform for rotation with the platform; a fixed shaft secured to the support frame and extending through the platform, the shaft carrying a gear meshing with an output gear within the gearbox, the output gear being rotatable by the shaft gear as the gearbox is rotated with the platform about the axis of the fixed shaft; and, a drive train coupled with said output gear and with at least one of said rollers for rotating the roller simultaneously with the rotation of the platform.

Conveniently, the input gear is arranged to be driven by a hydraulic motor, and this constitutes the sole power source which effects simultaneous rotation of the platform about its axis of rotation, (which extends generally perpendicular to the general plane of the support frame), and which will usually be a substantially vertical axis in normal use, and also causes rotation of at least one of the rollers so as to impart rotation to the bale.

The ring gear is a large ring gear and preferably of the type similar to so-called slew gears used with crane and jib structures mounted on turntables. The ring gear is preferably provided with an upwardly extending housing in the form of a "top hat" section which extends through a central hole in the platform. The gearbox is mounted within the housing, and preferably a recess is provided in the upper side of the platform in which the gearbox is entirely contained, so as not to project upwardly from the platform.

Conveniently, the upper surface of the platform is substantially flat, and preferably a cover is provided over the gearbox, so as to prevent bale material from coming into contact with the gearbox and components driven thereby.

In service, the ring gear and the housing attached thereto are caused to rotate, and this imparts rotation to the platform in which it is mounted. To provide a rigid structure for imparting rotation from the housing to the platform, it is preferred that one or more strengthening struts extend radially outwardly from the housing and are attached to the underside of the platform.

The drive train for the roller(s) may comprise a chain and sprocket drive to one or both rollers, drive input to this being provided by means of an output shaft coupled with the output gear in the gearbox. Suitable speed reductions will be provided in the overall drive train to the platform and to the rollers, so that the platform rotation, combined with the bale rotation, is such that the continuously supplied band of wrapping material is applied somewhat in spiral manner to the outer surface of the bale with progressive passes of the band overlapping each other, until such time as the entire bale is covered. The band can then be cut-off from the supply, and a suitable permanent attachment made to the now enclosed bale.

The support frame on which the platform is mounted will normally be located substantially horizontally, and a bale can be readily lowered into position on the rollers using a suitable lifting attachment on a tractor.

Following wrapping, the now enclosed bale can readily be removed by the same attachment of the tractor. However, if an automatic discharge facility is required, the support frame may be pivotally mounted on the base frame and provided with a suitable power operated mechanism, such as a pneumatic or hydraulic ram, which can effect upward pivoting of the support frame, and the platform carried thereby, in order to tip a wrapped bale which then falls under gravity from the receiving arrangement provided by the rollers. The support frame may then be returned to the substantially horizontal position, ready to receive a further bale.

To facilitate the application of rotation to the bale by the rollers, it is preferred that a continuous arrangement of one or more slack conveyor belts is taken around both rollers, and defines an arcuate (with respect to the axis of the bale) support which can engage a substantial portion of the periphery of the bale, and thereby readily apply rotation to the bale. However, the application of the conveyor belts is not essential, and it may be sufficient for the rollers to apply direct frictional force to the outer periphery of the bale, to impart rotation to the latter. To improve the frictional engagement with the bale, the rollers may be provided with suitable frictional surfaces or projections, such as ribs, to engage the bale.

Round bales are fairly dense and heavy bodies, and the platform and rollers have to be designed suitably robustly to bear this load, and to withstand reaction forces during rotation of the platform, and also the rotation of the bale. It is therefore important for the gear drive arrangement to be provided to be suitably robust. It is for this reason that a relatively large diameter ring gear is provided for imparting rotation to the platform.

Furthermore, the gearbox is a heavy duty gearbox, typically capable of transmitting up to 8 horse power in a reliable manner, this being considerably more than the power output required to drive the rollers.

In a typical arrangement, the ring gear, and therefore also the platform, can be rotated at about 20 revolutions per minute, and the rotation of the or each roller may be at a rate of about 10 cm of arc movement of the roller per revolution of the turntable. This arc of movement of 10 cm is at the outer periphery of the roller, for a roller of diameter approximately 21.25 cm. Alternative speeds of arcuate movement of the roller may be 15 cm or 20 cm per revolution of the turntable.

While a central gear drive to the platform is a significant feature in one aspect of the invention, it is within the scope of the invention for the drive means to the platform to take the form of a friction drive in the form of a friction wheel engaging with the underside or outer side of the platform at a substantial distance from its axis of rotation, thereby to impart rotation to the turntable.

The bale wrapper according to the invention may be used as a fixed installation, but preferably the base frame is wheel-supportedsfor transport purposes, or to enable the apparatus to be towed behind a tractor into a field in which round bales have been formed and then dumped.

One embodiment of bale wrapping apparatus according to the invention will now be described in detail, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a schematic side view of a bale wrapping apparatus according to the invention; Figure 2 is a schematic illustration of the gear drive arrangement to a rotating platform of the apparatus; Figure 3 is a schematic illustration of the output drive take-off; and, Figure 4 is a schematic illustration of a chain drive to one of the platform rollers.

There is disclosed herein a bale-wrapping apparatus having a rotatable platform on which a round bale can be supported during a wrapping operation, the platform being capable of taking-up a tilted position suitable for discharging a wrapped bale. On the underside of the platform, there is a drive arrangement for rotating the platform, and also for simultaneously applying rotation to one of a pair of rollers mounted on the platform.

The apparatus is primarily intended for wrapping a continuously supplied band of plastics material in a substantially helical fashion around the bale, this wrapping being achieved by continuously rotating the bale about a substantially vertical axis, simultaneously with rotation of the bale about its central substantially horizontal axis. This wrapping process is continued until such time as the bale is completely enclosed.

Therefore, the apparatus has a platform or turntable which is rotatable about a substantially~vertical axis, and the turntable carries a pair of laterally spaced-apart support rollers arranged with their axes parallel to each other and spaced apart by a sufficient distance so as to form a bale-holding arrangement.

The drive arrangement serves to apply rotation to the platform about its vertical axis, and extends from an input drive coupling with the platform so as to provide a drive train to one of the rollers.

Referring now to Figure 1, this shows schematically bale-wrapping apparatus 10 in accordance with the invention, which is intended to support a round bale 11 which is loaded thereon. A continuously supplied band 12 of plastics material is applied to the bale 11, and is wrapped around the bale 11 along a helical path, with subsequent turns overlapping, as the bale 11 carries out rotation about vertical axis 13 via its mounting on a platform 20, and also simultaneously rotating about its central horizontal axis 14. The apparatus 10 comprises a base 15 supported by wheels 16, and a support frame 17 is pivotally mounted on the base 15 via a pivot mounting 18.

A power operated device in the form of a ram 19 extends between the base 15 and the support frame 17, and is operable to effect pivoting of the support frame 17 about pivot mounting 18 to a tilted position, as shown in Figures 1 and 2. The platform 20 is rotatably mounted on the support frame 17 for rotation about axis 13 which extends generally perpendicular to the generar plane of the support frame 17, this axis being a vertical axis when the apparatus 10 is located on level ground.

A pair of rollers 21 are mounted on the platform 20 with their axes substantially parallel to each other and laterally spaced apart to form a bale-receiving arrangement onto which the round bale 11 can be placed so as to be held captive on the platform and with its axis 14 extending substantially parallel to the plane of the support frame 17 and usually substantially horizontally. Drive means is provided for rotating the platform 20 about its axis of rotation 13 with respect to the support frame 17, and for rotating the rollers 21 simultaneously with the rotation of the platform in order to rotate the bale 11, when supported by the rollers 21. Part of the drive means is shown in Figure 2, and another part is shown in Figures 3 and.4.

A dispenser 39 is mounted on the base 15 and is adapted to supply the band of wrapping material to wrap the bale, the band 12 being attached to the bale and being applied as a wrapping around the bale which progressively covers the bale as the platform 20 is rotated about axis 13 and simultaneously the bale 11 is rotated about axis 14 by the rollers 21. The part of the drive means shown in Figure 2 will now be described.

A drive coupling arrangement, designated generally by reference 23, is secured to the underside of platform 20, and takes the form of an input ring or slew gear 24 having an upstanding housing 25 in the form of a "top hat" section, which extends upwardly into the platform 20, to which it is secured. To apply rotation to the platform 20, radially outwardly extending struts 26 are secured to the housing 25 and also to the underside of the platform 20.

An input gear 27 applies input rotation to the ring gear 24, and is driven by a motor 28, which is preferably a hydraulic motor.

Referring now to Figure 3, there is shown means for transmitting drive to one of the rollers 21, simultaneously with the rotation imparted to the platform 20 by the ring gear 24. This comprises a stationary shaft 31 which is securely mounted in the support frame 17 and extends upwardly into a gearbox 30 which is mounted in a recess 29 provided in the upper surface of the platform 20, at the centre thereof. The gearbox 29 is housed within the housing 25 as well, and is arranged to rotate with the platform 20. A gear 32 is carried by the stationary shaft 31, and meshes within the gearbox 30 with an output gear 33, arranged at an inboard end of an output shaft 34.

A sprocket 35 is carried at the outboard end of shaft 34, and -transmits drive to one of the rollers 21 via a chain 36 and a sprocket 37 mounted on the hub of the roller 21. The ratios of the gearing arrangements shown are such that the platform 20 will normally rotate at approximately 20 revolutions per minute about axis 13, and simultaneously the driven roller 21 will carry out an arc of movement of about 10 cm per revolution of the platform 20, the roller 21 having a diameter of approximately 8 1/2 inches. Higher speeds of the roller 21 may be provided, if required, at 150%, or twice the angular speed just referred to.

It should be noted that the upper surface of platform 20 is flat, and a cover plate 38 is provided to close the recess 29, so as to prevent bale debris from becoming entangled with the drive mechanism.

Figures 1 to 4 are diagramatic drawings of the apparatus in a horizontal position of the platform, but this can be tilted by operation of ram 19.

To facilitate the transmission of rotation to the bale 11 by the rollers 21, an arrangement of slack conveyor belts or bands 22 are arranged on the rollers 21, and these enable a substantial surface area of frictional contact with the underside of the bale 11, to impart rotation thereto. However, it is not essential to provide bands 22, provided that adequate frictional contact is provided between the rollers 21 and the bale 11. This may be achieved by, for example, suitable frictional surfaces on the rollers, or circumferentially spaced ribs extending from one end to the other of the rollers.

The disclosed arrangement of gear drive input for rotating the platform 20 is of robust construction, having regard to the substantial weight of a round bale, and the substantial inertia forces which will be generated during rotation of the bale, both about vertical axis 13, and also about horizontal axis 14. The gearbox 30 is capable of transmitting up to 8 horse power, which is considerably more than the normal power demand of the apparatus. While the central gear drive input is a preferred arrangement, it is within the scope of the invention to provide a friction drive which engages the underside of the platform 20 at a suitable spacing from the axis 13, or it may engage the outer periphery.

The apparatus 10 may be intended for use as a substantially fixed installation, or it may be towed into a field for use on freshly deposited round bales.

The dispenser 39 is a proprietory piece of equipment, known as a pre-stretch unit, which is able to pre-stretch plastics film by up to 55% prior to wrapping onto the bale, and this enables the bale to be tightly wrapped and to give a very even and secure wrapping, so that the wrapped bale can withstand adverse weather conditions.

Claims (12)

1. A bale-wrapping apparatus which comprises a base; a support frame mounted on the base; a platform rotatably mounted on the support frame for rotation about an axis extending generally perpendicular to the general plane of the support frame; a pair of rollers mounted on the platform with their axes substantially parallel to each other and laterally spaced apart to form a bale-receiving arrangement onto which a round bale can be placed so as to be held captive on the platform and with its axis extending substantially parallel to the plane of the support frame; and drive means for rotating the platform about its axis of rotation with respect to the support frame, and for rotating the rollers simultaneously with the rotation of the platform in order to rotate the bale, when supported by the rollers; and, a dispenser mounted on the base and adapted to supply a band of wrapping material to wrap the bale, the band being attached to the bale and being applied as a wrapping around the bale which progressively covers the bale as the platform is rotated about its axis and the bale is rotated about its axis by the rollers; in which the drive means comprises:: a ring gear secured to the underside of the platform for rotation therewith; an input gear coupled with the ring gear; a gearbox mounted on or in the upper side of the platform for rotation with the platform; a fixed shaft secured to the support frame and extending through the platform, the shaft carrying a gear meshing with an output gear within the gearbox, the output gear being rotatable by the shaft gear as the gearbox is rotated with the platform about the axis of the fixed snaft; and, a drive train coupled with said output gear and with at least one of said rollers for rotating the roller simultaneously with the rotation of the platform.

2. Apparatus according to Claim 1, in which the input gear is arranged to be driven by a hydraulic motor, and this constitutes the sole power source which effects simultaneous rotation of the platform about its axis of rotation, and also causes rotation of at least one of said rollers so as to impart rotation to the bale.

3. Apparatus according to Claim 1 or 2, in which the ring gear is a large ring gear.

4. Apparatus according to Claim 3, in which the ring gear is provided with an upwardly extending housing in the form of a "top hat" section which extends through a central hole in the platform.

5. Apparatus according to Claim 4, in which the gearbox is mounted within said housing, and a recess is provided in the upper side of the platform in which the gearbox is entirely contained, so as not to project upwardly from the platform.

6. Apparatus according to any one of the preceding claims, in which the upper surface of the platform is substantially flat, and a cover is provided over the gearbox, so as to prevent bale material from coming into contact with the gearbox and components driven thereby.

7. Apparatus according to Claims 4 or 5, in which one or more strengthening struts extend radially outwardly from the housing and are attached to the underside of the platform.

8. Apparatus according to any one of the preceding claims, in which the drive train for the roller(s) comprises a chain and sprocket drive to one or both rollers, drive input to this being provided by means of an output shaft coupled with the output gear in the gearbox.

9. Apparatus according to any one of the preceding claims, in which the support frame is pivotally mounted on the base frame and is provided with a suitable power operated mechanism which can effect upward pivotting of the support frame, and the platform carried thereby, in order to tip a wrapped bale which then falls under gravity from the receiving arrangement provided by the rollers.

10. Apparatus according to any one of the preceding claims, in which a continuous arrangement of one or more slack conveyor belts is taken around both rollers, and defines an arcuate support which can engage a substantial portion of the periphery of the bale, and thereby readily apply rotation to the bale.

11. Apparatus according to Claim 10, in which the rollers are provided with suitable frictional surfaces or projections to engage the bale.

12. Apparatus according to Claim 1 and substantially as hereinbefore described with reference to, and as shown in the accompanying drawings.