A METHOD AND A DEVICE FOR WRAPPING WITH WEB-SHAPED MATERIAL

Abstract: A method for packing bodies (3), e.g. fodder bales of a generally cyclindrical or parallelepipedic configuration, in continuous material, such as plastics, comprising a support of the body and a winding of continuous material around the body from at least one magazine with continuous material while rotating the body around a first axis (7) of the body by means of a roller arrangement including at least one rotatably arranged roller device. The method is especially characterized in that at least one roller device (5'), downwards to which the body envelope surface (9) then rotates, is adapted to approach the body envelope surface. The invention also relates to a device for packing bodies.

Description: A method and a device at wrapping by web-shaped material The present invention relates to a method for packing bodies, e.g. fodder bales with an essentially cylindrical or parallelepipedic configuration, in a continuous material, such as continuous plastics, comprising to support the body and winding the continuous material around the body from one or several magazines for continuous material while rotating the body around a first axis of the body by means of a roller arrangement, comprising at least one rotatably arranged roller device. The invention relates also to a device for performing the method. ' Methods of essentially the above mentioned type are already known. According to such a known method a body, such as a bale, is supported on a table with two axially parallel and at a distance from each other arranged rolls, between which continuous belts or stripes are run¬ ning. The bands are arranged to rotate the bale around said first axis being essentially parallel to the roller axes. An essential problem with bales with a square or a rectangular cross section across said first axis exists, in that the bale circumferential speed is varying during each turn. From a position with the bale resting on a corner, the bale thus tilts, parts of the bale periphery then having a speed surpassing that for a normal driven rotation. This results in a varying overlapping of the continuous material, the plastics, wrinkling at the bale end portions as well as highly undesired thrust stresses in the structure, when the bale hits the roll lying in the til¬ ting direction. Bale rotation will also become more energy consuming than necessary, when the bale must be lifted to a greater extent, when the corner/edge hits the belt. The bales might have a weight over 500 kg/m 3 , the tendecy being to even larger bale weights. The present invention relates to a solution of the above described problems. Thus, the invention relates to a method according to the ingressing part of the attached claim 1. The method is especially characterized by what is stated in the characterizing part of said claim. The invention also relates to a device according to the ingressing part of the attached claim 9. The device is especially characterized by what is stated in the characterizing part of said last mentioned claim. The invention will be described more in detail in connection with execution examples and the attached drawings, in which Figure 1 schematically shows a view of a first embodiment of a device for winding continuous material around a body, such as a fodder bale, Figure 2 schematically shows a first embodiment of a device according to the invention seen in the direction of a first body axis and likewise of the rotation axis of roller devices ar¬ ranged to cooperate when rotating and supporting the bodies, Figure 3 schematically shows the device of figure 2 with the body and a roller device in a position different from figure 2, Figure 4 schematically shows another embodiment of a device according to the inven¬ tion seen as the device according to figures 2 and 3, Figure 5 schematically shows a third embodiment , essentially corresponding to the one shown in figure 4, and Figure 6 schematically shows a hydraulic arrangement for damping, etc. In figure 1 a known device is designated with 1 for winding continuous material 2 around a body 3, such as a fodder bale, for packing. The embodiments of such devices are described e.g. in the Swedish patent 9101032-2. With 4 is designated a support for a body, comprising two roller devices 5, rolls 5, between which at least one continuous belt drive 6 is running for cooperation during a support of the body and for rotating the body around a first axis 7 of the body. According to the embodiment shown here, the body is also rotatable around a second axis 8 of the body, this axis 8 being generally perpendicular to said first axis. The problems the invention aims to solve are related to the rotation of the body, the bale, around said first axis. As to the method of winding and packing itself, there are several variations, to which the invention can be applied. During winding according to figure 1 successive turns are wound around both the long sides 3' of the body and its end portions 3", rotating the body around said first axis and said second axis, at least one magazine 2' for continuous material being provided stationary. According to another embodiment (not shown) the rotation of the body is performed around said first axis, while the magazine(s) is caused to rotate around the body by means of a bracket supporting the magazine(s) or similar. According to said Swedish patent the windings described therein are preferably supplemented by a crossing winding (not shown), the continuous material being arranged to contact the body across said first axis, thereby crossing the body long sides. According to the present invention at least one, e.g. 5', of said roller devices 5, is ar¬ ranged risingly and fallingly, i.e. the one, in the direction towards which the body circumfe¬ rence or upper side 9' of the envelope surface 9 is arranged to move during the rotation of the body, and down towards which the body circumference is moved, as indicated by an arrow 10 in figure 3, to meet the body circumference during rotation to comply with the variations in the body circumference configurations and to prevent or counteract any variations in the speed of the body envelope surface 9 and the body rotary speed. Then, the rising and falling roller de¬ vice 5'is generally following the body circumference and prevents a body with a square, rectangular or similar cross section to tip from a position resting on a comer, see figure 3. Otherwise an uneven overlapping is achieved of the continuous material as well as shocks against the roller device. According to the first embodiment shown in figure 2 and 3 the roller device or the roll 5' is displaced in relation to the circumference of the body upper side, thereby pushing the lower circumference of the bale in towards a device portion 11 between the two relatively generally parallel roller devices 5, pivotingly supported by means of link devices 12 for achieving a rising and falling. Thus, the roller device 5' is preferably suspended at each and portion 13 by means of a link device extending from a swivelling center 14, preferably arranged substantially below a track 15, in which runs the lower portion 16 of said belt drive(s). According to a pre¬ ferred embodiment the link devices, here shown as simple brackets or bars, are besides by the roller device connected by means of a boom device 12' running between the link devices, the boom then generally stretching parallelly to the roller devices. The boom device is also ar¬ ranged to support a rider 17 for controlling one or several belt drives, see figure 2. In many cases it is also preferred that said pivoting center is situated assymmetrically in relation to the roller devices and thus closer to the rising and falling roller device 5', e.g. in such a way that the distance between the pivoting center and the center of the rising and falling roller device is about 40 percent of the total distance L between the roller devices 5. In the vertical direction the distance between the pivoting center and the lower belt drive is preferably about 120 mm, the belt drive then running generally horizontally, see figure 2, altogether with a bale side length of 800 to 1000 mm in the view shown in figure 2. The purpose of this arrangement is that the tension in the drive(s) by the bale weight is lifting the roll 5', the drive(s) then slack¬ ening and possibly swallowing the bale comer without lifting the bale, thus saving energy. This effect is increased by placing the stationary roller device or the roll 5 higher or providing it with a larger diameter corresponding approximately a larger swallowing height with the body dimension. Such an arrangement can be adjusted so that the bale center axis 7 is not moving up and down during any bale rotation. Such an arrangement with a larger diameter of the stationary roller device is schematically shown and drawn with dashed lines in figures 2 and 3. With 12" are designated devices cooperating with said link devices, such as resilient and damping piston and/or spring devices, for a damping, essentially for absorbing shocks from the body against the approaching roller device 5 '. In this way a combination of a hydraulic shock absorber and a pressure spring can be used. According to the second embodiment shown in figure 4 said support and the roller de¬ vices 5 connected to the support are together pivotably and tiltably arranged preferably around a pivoting center 18 arranged between the roller devices for said adaptation by means of rising and lowering, as indictaed in figure 4. According to at least this embodiment there are devices 19 of a convenient known type for detecting the position of the body circumference, e.g. in relation to said risingly and fallingly approaching roller device 5' as well as devices (not shown) for controlling said pivoting or for controlling a corresponding tilting of said rising and falling in relation to the position of the body circumference for said adaptation devices 20, such as one or several hydraulic cylinders 20, being provided to achieve a pivoting or tilting according to said control. Even here suitable resilient devices 12' are provided for a damping, as indicated in figure 4. The devices sensing the body position can e.g. be mechanical devices (not shown), such as a bracket or similar, being by means of a switch or similar arranged to detect e.g. the vertical position of the upper belt drive, in relation to the body position, as might be seen by comparing figures 2 and 3. In case the support is tillable itself to tilt already packaged bodies it might be considered to combine this feature with said pivoting around the same pivoting center 21, see figure 5, the pivoting center 18 possibly lying outside of the portion 11 between the roller devices. The devices 20 for achieving said adaptation are here conveniently also used as tilting devices. In embodiments with hydraulic devices 20 for said approach these might be combined with i.a. any damping arrangements, e.g. in accordance with figure 6. According to one em¬ bodiment the hydraulic piston 20 is then on its operative side, port A, connected to an oil gas accumulator 22 by means of a throttling valve 23, the damping then being performed towards the oil gas accumulator. The return side of the piston 20, port BODY, is also adapted to be pressurized for a return, the rising and falling roller device 5' then being returned to a lower, properly defined position. According to a preferred embodiment comprising devices for packing items (not shown), generally according to the Swedish patent 9301086-6 to keep the continuous material ap¬ proaching the body envelope surface during cutting of the continuous material for a final winding, the winding thus being terminated with a turn of the crossing kind running across said first axis. These devices are preferably arranged to be activated by means of at least one hydraulic cylinder for operating brackets or similar, the hydraulic system then being arranged so that hydraulic devices 20 are synchronically activated, when devices for supporting the continuous material are activated, arranged for said rising and falling for said adaptation to lower to achieve properly defined conditions, i.a. regarding the position in combination with a gripping, etc. of the continuous material . The lowering is conveniently performed via said return side, port B. The method as well as the operation of said device according to the invention is sub¬ stantially evident from what is stated above. According to the basic principle, therefore, a roller device or roll is arranged, so that it approaches the envelope surface of the body, the bale, on its way downwards during a rotation of the body to prevent variations in speed and to minimize any shocks in the structure. Espe¬ cially, a body standing on its comer is prevented to tip freely, when it is tilted over from an unstable position, when resting on its comer. In the embodiment according to figures 2 and 3 and similar embodiments with the body supported and rotated by means of one or several belt drives, a generally self adjusting system is achieved and the roller devices arc pivotably supported in a suitable shown way. The body weight is creating tensile stresses in a belt drive between the roller devices, said tenile stresses tending to rise the roller device 5', conveniently pivotably and suitably arranged. In the tran¬ sition from the position shown in figure 2, where the roller device 5' is loaded by the body, to the position shown in figure 3, a component of the tensile force due to the position of the pi¬ voting center to successively rise the roller device 5' will thereby approach the comer 3' of the body on its way downwards, thereby preventing the body to uncontrollably tilt from its posi¬ tion, when standing on one comer. The operation of the embodiment according to figures 3 and 4 is subtsantially the same, however, no self control is achieved, but any rising or falling is controlled in relation to the detected body position. As will also be evident from what is stated previously, the invention provides essential advantages compared with what is known in the art. Thus, an essential reduction is achieved in service and repair due to lower stresses in the device. Moreover, a more even distribution of the packing material is achieved resulting in better quality. Moreover, the productivity is increased, as the winding speed can be augmented, espe¬ cially when winding across said first axis, i.d. in applying a cross winding according to above mentioned Swedish patent. The stresses due to shocks etc. are generally restricting the maxi¬ mum allowed rotary speed of the body. The invention has been described above in connection with several execution examples. Of course, further embodiments and minor changes and amplifications might be endeavoured without departing from the scope of the invention. Embodiments generally according to figures 2 and 3 can of course be envisaged with the body position being detected and said rising and falling being controlled in relation to said position as with the embodiments according to figures 3 and 4. Embodiments might also be envisaged with the body not being supported by means of belt drives, but e.g. by means of several rolls arranged along a cylinder or in some other con¬ figuration. Also for devices with belt drives roller devices might be envisaged, such as plane¬ tary type devices.

Claims: Claims 1. A method for packing bodies, e.g. fodder bales of a generally cylindrical or paralle¬ lepipedic configuration, in continuous material, such as plastics, comprising a support of the body and a winding of continuous material around the body from at least one magazine with continuous material while rotating the body around a first axis of the body by means of a roller arrangement including at least one rotatably arranged roller device, characterized in that at least one roller device (5'), downwards to which the body envelope surface (9) then rotates, is arranged to approach the body envelope surface. 2. A method according to claim 1, characterized in that the body (3) is supported by means of two separately arranged roller devices (5), of which at least one (5') is adapted to be rised and lowered for said approach. 3. A method according to claim 1 or 2, characterized in that the own weight of the body and/or profile is used to achieve a rising and lowering of at least one roller device (5'). 4. A method according to claim 1, 2 or 3, with the body supported by means of a belt drive running between at least two roller devices, characterized In that said rising and falling roller device (5') is pivotably arranged and adapted to be rised and lowered on said belt drive(s) (6) by the effect of the body. 5. A method according to claim 4, characterized in that the pivotably arranged roller device (5) is adapted to pivot around a pivoting center (14) preferably arranged substantially under a track (15), in which the lower protion (16) of said belt drive(s) is running. 6. A method according to claim 4 or 5, characterized in that the pivotably arranged roller device (5') is adapted to pivot around an assymmetrically arranged pivoting center (14), po¬ sitioned at less than half the distance (L) between the roller devices (5) from said pivotably arranged roller device (5'). 7. A method according to claim 1, 2, 3, 4, 5 or 6, characterized in that both said support (4) and the roller devices (5) connected to the support are pivotably or tiltably arranged and are adapted to pivot for said approach. 8. A method according to claim 1, 2, 3, 4, 5, 6 or 7, characterized in that the body posi¬ tion in relation to said rising and falling roller device is detected, the rising and lowering of said roller device being performed in relation to the body position for said approach by means of devices (20) for said rising and lowering. 9. A method according to claim 1, 2, 3, 4, 5, 6, 7 or 8, characterized in that said rising and lowering is supplemented by a damping, mainly for compensating shocks from the body, and preferably by resilience cooperating during said approach. 10. A method according to claim 9, characterized in that said damping is performed by means of at least one hydraulic piston (20) the operating side of which, port A, is connected to an oil gas accumulator (22) and a return throttling valve (23). 11. A method according to claim 10, characterized in that said return side of the hyd¬ raulic piston, port B, is pressurized for reraming the rising and falling roller device (5') to a lower position. 12. A method according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11, with the continuous material being gripped and supported by means of suitable devices in a position across said first axis against the approaching body position in connection with a final winding and cutting of the continuous material, characterized in that the gripping and supporting is synchronized with said rising and lowering so that said risingly and fallingly arranged roller devices (5') are lowered to a lower position by means of suitably adapted devices (20) in connection with an initiated gripping and supporting. 13. A device for packing bodies, e.g. fodder bales of a generally cylindrical or paralle¬ lepipedic configuration, in continuous material, such as continuous plastics, comprising de¬ vices to support a body and devices for winding continuous material around the body from at least one magazine for continuous material and to rotate said body around a first axis of the body by means of a roller arrangement, characterized in that at least one rotatably arranged roller device (5') is risably and fallingly arranged and adapted to approach the body (3) en¬ velope surface (9) during its rotation downwards. 14. A device according to claim 13, characterized in that two roller devices (5) are provided, being separated and preferably parallel, at least one of these being risably and fal¬ lingly arranged for said approach. 15. A device according to claim 13 or 14, characterized in that devices (5', 6) are pro¬ vided to use the body weight and/or profile to achieve a rising and lowering of at least one roller device (5'). 16. A device according to claim 13, 14 or 15, with the body adapted to be supported by means of at least one continuous belt drive running between at least two roller devices, cha¬ racterized in that said rising and falling roller device (5') is pivotably adapted to be rised and lowered on said belt drive(s) by the body effect. 17. A device according to claim 16, characterized in that devices, such as at least one link device (12) is provided, by means of which the pivotably arranged roller device (5') is pivo- table around a pivoting center (14), preferably situated substantially below a track (15), in which the lower portion (16) of said belt drive(s) is running. 18. A device according to claim 16 or 17, characterized in that the pivoatbly arranged roller device (5') is adapted to pivot around an assymmetrically arranged pivoting center (14), lying at less than half the distance (L) between the roller devices (5) from the pivotably ar¬ ranged roller device (5'). 19. A device according to claim 17 or 18, characterized in that the risingly and fallingly arranged roller device is preferably and rotatably supported at each end portion (13) by means of a link device (12) running from said pivoting center (14), the link devices being besides by means of the roller device preferably connected by means of a boom device (12') running between the link devices. 20. A device according to claim 13, 14, 15, 16, 17, 18 or 19, characterized in that said support (4) with roller devices (5) supported by means of the support are together pivotably arranged for said approach by means of rising and lowering. 21. A device according to claim 13, 14, 15, 16, 17, 18, 19 or 20, characterized in that devices (19) are provided for scanning the position of the body (3) envelope surface (9) in re¬ lation to said rising and falling roller device as well as devices for adjusting said rising and lowering in relation to the position of the body envelope surface for said approach, devices (20) being provided to achieve said rising and lowering. 22. A device according to claim 13, 14, 15, 16, 17, 18, 19, 20 or 21, characterized in that the devices for said rising and lowering are supplemented by devices (20, 21, 22, 23) for a damping, preferably for compensating shocks from the body against the approaching roller device (5') and preferably also devices (21) for resilience, adapted to cooperate during said approach. 23. A device according to claim 22, characterized in that at least one hydraulic piston (20) is provided for said damping with its operative side, port A, connected with an oil gas accumulator (22) and a return throttling valve (23). 24. A device according to claim 23, characterized in that said hydraulic piston return side, port B, is adapted to be pressurized for returning said rising and falling roller device (5') to a lower position. 25. A device according to claim 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 or 24 with de¬ vices provided for gripping and supporting said continuous material in a position running across said first axis towards the bodyin connection with the final winding and cutting of said continuous material, characterized in that devices are provided to synchcronize thedevices for said gripping ans supporting with devices (20) for said rising and lowering, so that said rinsingly and fallingly arranged roller devices (5') are lowered to a lower position by means of devices (20) adapted for this purpose in connection with a initiated gripping and a supporting, the gripping and supporting possibly performed under well defined conditions.

Inventors: SOEDERBERG STAFFAN, SOEDERBERG, STAFFAN
Applicants: SOEDERBERG STAFFAN, SOEDERBERG, STAFFAN
Application year: 1996
Main classification: B65B11
IPC codes: A01F15, B65B11