EP1053939A1

EP1053939A1 - Apparatus for providing netting packages of horticultural products in continuously unwound tubular netting

Info

Publication number: EP1053939A1
Application number: EP00110172A
Authority: EP
Inventors: Andrea Mercadini; Vincenzo Pieri
Original assignee: Sorma SpA
Current assignee: Sorma SpA
Priority date: 1999-05-17
Filing date: 2000-05-15
Publication date: 2000-11-22
Also published as: ITBO990260A1; ITBO990260A0; IT1309251B1

Abstract

An apparatus for producing packages of horticultural products with tubular netting (42) which is unwound continuously from a reel, said apparatus comprising a frame (1), a tube (40) which is vertically suspended from said frame and inside said netting (42), said tube (40) having a lateral opening (47, 72) for loading the products which is aligned with the outlet of a product feeder (37), a cutting device (50) which is suitable to produce a slit (54a) in said netting in order to allow to load products inside said tube (40) through said slit (54a) and said opening (47, 72), characterized in that it comprises means (24-27, 30, 31, 48, 49) for controlling the sliding of said netting (42) on said tube (40) by an extent which defines a bag (S) for containing the products and means (14, 15) for closing said tubular netting (42) below said tube (40) according to two stacked closures (62, 63, 64), an upper closure (62) forming the bottom of said bag (S) and a lower closure (63, 64) closing the previously formed bag, means (14a, 15a) being further provided for cutting said netting (42) between said upper and lower closures (62 and 63, 64).

Description

The present invention relates to an apparatus for providing packages of horticultural products using tubular netting unwound continuously from a reel.
Various packaging machines are known for packaging horticultural products in netting which generally have a tube on which a preset amount of tubular netting, which depends on the length of said tube, is arranged beforehand. The netting is closed at its lower end, so as to form a bag for collecting the products that enter from the top of the tube. The bag containing the products is then removed from the tube in order to form the packages, which are then closed and mutually separated. These machines periodically have to stop in order to allow replacement of the depleted netting holder tube with another spare one loaded with the tubular netting.
The netting holder tubes are loaded manually or with semiautomatic devices, and loading in any case requires the intervention of an operator who, in addition to overseeing the filling operation, must replace the tubes in the machine.
US Patent no. 4,091,595 discloses a method for producing packages of horticultural products or the like enclosed in a tubular netting unwound continuously from a reel on which it is wound. In this method, the netting is conveyed through means which give it a tubular shape and close its lower end with a heat-sealable card so as to form a bag with a closed bottom. A slit is then formed in said tubular netting so as to not interrupt its continuity and at a preset distance from the closed bottom. A preset quantity of products is introduced in the bag through the slit. After removing the bag and severing it, at its top, from the remaining part of the tubular netting, the mouth of the bag is closed with a band which is wound in a noose-like fashion around it.
With this conventional method, the closure of the bag and of the bottom requires auxiliary devices which have a low capacity due to the presence of considerable idle times.
The aim of the present invention is to provide an apparatus which can perform packaging in netting so as to avoid the drawbacks of conventional packaging machines.
This aim is achieved with an apparatus whose characteristics are defined in the claims. Further characteristics will become better apparent from the following detailed description of an apparatus according to the present invention, illustrated only by way of non-limitative example in the accompanying drawings, wherein:
Figure 1 is a front elevation view of the apparatus according to the present invention;
Figure 2 is a sectional lateral elevation view of the apparatus, taken along the line II-II of Figure 1;
Figure 3 is a plan view of the apparatus;
Figure 4 is an enlarged-scale view of a part of the apparatus;
Figure 5 is a perspective view of a detail of the apparatus;
Figure 6 is a view of a package which can be obtained with the apparatus of the preceding figures;
Figure 7 is a schematic view of a second embodiment of the apparatus according to the present invention;
Figure 8 is a view of a third embodiment of the present invention;
Figures 9 and 10 are views of a fourth embodiment of the present invention; and
Figure 11 is a view of a fifth embodiment of the present invention.
With reference to the above figures, the apparatus according to the invention comprises a framework 1 with two mutually opposite walls or sides 2 and 3, from each of which two upper brackets 4 and two lower brackets 5 protrude. Each lower bracket 5 is vertically aligned with a respective upper bracket 4.
Two vertical rods 6 are fixed between the brackets 4 and 5 of the left side in Figure 1. Two identical vertical rods 7 are fixed between the brackets 4 and 5 of the right side 3. The rods 6 and 7 are arranged at the corners of an imaginary rectangle, and respective sprocket wheels 8 are engaged thereon and mesh with a chain 9 which is closed in a loop around them.
The sprocket wheels 8 (Figure 3) are rotatably supported at the corners of a rectangular frame 10 which lies around the threaded rods 6 and 7. The sides of the frame that lie between the walls 2 and 3 are designated by the reference numerals 10a and 10b and the two sides that are perpendicular thereto are designated by the reference numerals 10c and 10d.
A reversible gearmotor 11 is mounted on the side 10c, and a pinion 11a (see Figure 3) is keyed on the output shaft of said gearmotor and meshes with the chain 9. Accordingly, by actuating the gearmotor 11 in one direction or the other, all the sprocket wheels 8 move along the thread simultaneously and the frame 10 rises or descends.
The two sides 10c and 10d of the frame 10 are mutually connected by two parallel bars 12a and 12b on which two carriages 13a and 13b slide. The carriages 13a, 13b support respective pairs of heat-sealing jaws 14 and 15 which are actuated by actuation means in order to be moved mutually closer or further apart. As also shown in Figure 7, the actuation means comprise a cylinder 16a which actuates a lever 16b which is pivoted in a rocker-like fashion in the frame 10 and whose opposite ends are connected to the carriages 13a, 13b by traction elements 16c, 16d. A blade 14a, 15a of a cutting device (Figure 4) is arranged between the jaws of each pair.
In the figures, the heat-sealing jaws and the cutting device are not shown in detail, since they have a conventional construction which has already been used in other packaging machines. However, the jaws 14 and 15 are conceived so that when they are moved mutually closer the material that will constitute the enclosure of the package and is guided between them is clamped and heat-sealed along two overlapping heat-sealing lines, while the blades 14a, 15a sever the material between the heat-sealed regions that have been formed.
The framework 1 forms, at the top, two shoulders 17a, 17b (Figure 4) between which two stacked bars 18 and 19 lie for supporting two plates 20, 21. The plates 20, 21 can slide on the bars 18, 19 (for example by means of a jack 80, as shown in the version of Figure 7) so as to be able to adjust their position with respect to a tube 33 which is guided between them. Two respective units are mounted on the plates 20 and 21 and are arranged to control the sliding of the tubular netting 42 from which the packages are formed, as will become apparent hereinafter. The units comprise respective upper pivots 22, 23 (Figure 4) which cantilever out from the plates 20, 21 and on which rollers 24, 25 are rotatably supported. Two additional rollers 26, 27 are arranged below the rollers 24, 25. The rollers 26, 27 are connected to respective gearmotors 28, 29 which are mounted on the plates 20, 21.
Respective belts 30, 31 are wound in a loop around the rollers 24, 26 and 25, 27 and are arranged to feed the netting 42 when, as will become better apparent hereinafter, the front portions of the belts advance downward. Advantageously (see the embodiment of Figure 7), the gearmotors 28 and 29 are mutually connected by a telescopic cardan shaft 29a which allows the mutual spacing of the gearmotors and ensures that the belts 30 and 31 move at the same speed.
The pairs of rollers 24, 26 and the front portion of the belt 30 wound on them are partially inserted in an opening 32 of a vertical tube 33 which lies in front of them. The vertical tube 33 conveniently has a square crosssection and has a flange 34 by means of which it is fixed to the top of the framework 1.
The opening 32 is formed on one face of the tube 33 and is arranged opposite another identical opening 35 formed on the opposite face.
The rollers 25, 27 and the corresponding front portion of the belt 31 partially enter said second opening 35.
An additional rectangular opening 36 is formed in one of the two remaining faces of the tube 33, at a lower level than the openings 32 and 35, and a conveyor 37 (Figure 2) for feeding the products to be packaged leads to said opening and is supported by walls 38 which cantilever out from the framework 1. Above the conveyor 37 a wall 39 is provided which acts as accumulation abutment for the products conveyed by the conveyor 37 and is actuated, in any manner (not shown), so as to rise in order to allow the accumulated products to fall through the opening 36.
A second tube 40 (Figure 2) is inserted inside the tube 33, has a square cross-section but is smaller than the tube 33, so that a gap 41 (Figure 4) remains between the tube 33 and the inner tube 40; the gap is wide enough to slide through it, from the top downward, a flexible tubular element, particularly tubular netting 42 which constitutes the enclosure for containing the products to be packaged.
The inner tube 40 floats inside the tube 33, i.e., is free to perform small vertical movements, and can rest on the flange 34 by means of a peripheral step 43 from which it protrudes upward with an ogive 44.
The inner tube 40 has, on two opposite faces, respective openings 45, 46 which faces the openings 32, 35 of the outer tube.
A third opening 47 faces the opening 36. The dimensions of the openings 45, 46 and 47 are substantially identical, in terms of shape and dimensions, to those of the openings 32, 35 and 36.
Two freely rotating contrast rollers 48 and 49 are supported inside the inner tube 40, are parallel to the rollers 24-27, and partially protrude outward through the openings 45, 46 of the inner tube and the openings 32, 35 of the outer tube 33. The contrast rollers 48, 49 engage portions of the belts 30, 31 that lie between the upper rollers 22, 25 and the lower rollers 26, 27 so that belts 30, 31 wind, along said portions and over a certain angle, around the contrast rollers 48, 49, tracing an undulated path.
The above-described apparatus is completed by a cutting device 50 which is arranged under the outlet of the conveyor 37 and is constituted by a blade 51 which is actuated intermittently by a pneumatic actuator 52 and is orientated so as to pass through the openings 36 and 47.
The operation of the apparatus is as follows.
First of all, the tubular netting 42 is unwound from a reel 53 through a plurality of guiding rollers 54 and is arranged around the inner tube 40, making it pass along the gap 41 between the inner tube 40 and the outer tube 33 and between the contrast rollers 48, 49 and the belts 30, 31. Conveniently, in order to facilitate this step for applying the netting to the tube 40, the belts 30, 31 are moved away from the contrast rollers 48, 49 by moving the plates 20, 21 that support the gearmotors 28, 29 along the bars 18, 19.
Once the end of the netting 42 has passed below the lower end of the outer tube 33 and is arranged between the heat-sealing jaws 14 and 15, the plates 20, 21 are moved toward each other again, so that the contrast rollers 48, 49 engage between the rollers 22-27 and the netting 42 remains engaged between the contrast rollers 48, 49 and the belts 30, 31. This engagement also ensures the separation of the step 43 from the flange 34 and the floating support of the inner tube 40. Once these preliminary preparatory operations have been completed, the jaws 14, 15 are moved mutually closer and close the tubular netting with a heat-sealing line, which thus forms the bottom S (Figures 1 and 4) of a product containment bag which is constituted by the lower portion of the tubular netting 42.
At this point, the cutting device 50 is activated; its blade 51, by passing through the openings 36, 47 of the tubes 33 and 40, respectively, cuts into the netting, forming a transverse slit 54a (see Figure 5) through which, after actuating the lifting of the wall 39, a preset amount of products is conveyed into the inner tube 40, stopping on the closed bottom of the netting bag 42 and resting on the plane formed by the jaws 14, 15.
By spacing the jaws 14, 15 by way of the mutual spacing of the carriages 13a, 13b produced by the jack 16a, the bag that contains the product and is still wrapped around the inner tube 40 remains suspended between the rollers 48, 49 and the belts 30, 31. The subsequent step is then started and consists in actuating the units 28, 29 that drive the rollers 22-27 so as to allow the bottom S to descend until it forms a bag which contains the products below the jaws 14, 15. The descent stroke of the bag ends when the gearmotors 28 and 29 stop and the netting is locked between the rollers 22-27 and the rollers 48-49.
As soon as the descent stroke of the bag stops, the stroke for the mutual approach of the jaws 14, 15 is actuated so that the lower heat-sealing line closes the bag in an upward region and the upper heat-sealing line closes the tubular netting so as to form the bottom of a new bag. The extent of the descent stroke is such that the slit 54a is arranged between the two upper and lower heat-sealing lines.
At the same time, a cut for severing the tubular netting 42 is performed by the blades 14a, 15a between the two heat-sealing lines and on the slit 54a and allows, by way of the spacing of the carriages, to unload the formed package 55. The apparatus can thus resume the production cycle according to the above described steps.
It should be observed that by acting on the gearmotor 11 it is possible to raise or lower the level of the frame 10 and therefore of the heat-sealing jaws 14, 15. At the same time, by adjusting the intervention times of the gearmotors 28 and 29 it is possible to increase or decrease the length of the bag that is removed from the tube 40 in order to obtain packages having the chosen length and, accordingly, the chosen capacity.
It is evident that the above-described apparatus fully achieves the intended aim. In particular, it is noted that no preparation of the tubular packaging netting on a netting supporting tube is required; the tubular netting can instead be fed from a reel so as to ensure a comparatively much longer autonomous operation than obtainable with conventional packaging machines.
The above-described apparatus is susceptible of numerous modifications and variations.
In one embodiment of the present invention, the gearmotors 28, 29 are replaced with friction assemblies and the bag that contains the products is lowered by actuating with a reciprocating motion the frame 10 and using the jaws 14, 15 like a clamp.
In this embodiment, the netting 42 is closed when the jaws 14, 15 are in a raised position.
The subsequent step is then started and consists in actuating the gearmotor 11, which by means of the chain 9 moves the sprocket wheels 8 along the thread of the threaded rods 6 and causes the descent of the frame 10. Since the jaws 14, 15 are still in the clamping position, the bag descends by a preset extent.
It should be observed that the descent stroke of the bag is braked by the rollers 22, 27 and the contrast rollers 48, 49, so that the traction force applied to the net, by acting on the step 43, allows the upward movement of the inner tube 40 and the controlled descent of the bag.
As soon as the descent stroke of the bag has ended, the jaws 14, 15 are spaced again and the frame 10 is returned to the upward position so as to allow the jaws to reposition themselves above the bag, which at this point is retained between the rollers 22-27 and the contrast rollers 48, 49.
The frame 10 is raised by reversing the direction of rotation of the gearmotor 11 and therefore of the sprocket wheels 8. The cycle is completed by closing the jaws on the netting above the bag, so that the lower heatsealing line closes the bag and the upper heat-sealing line forms the bottom of a new bag. At the same time, the blades 14a, 15a form, between the two heat-sealed regions, a severing cut which allows, when the carriages are spaced, to unload the formed package 55 (see Figure 1).
The apparatus can thus resume its production cycle according to the above described steps.
Figures 1 and 6 illustrate the possibility to associate with the opposite sides of the package 55 two bands 56, 57 which are taken from respective reels 58, 59 and are conveyed by guiding rollers 60, 61 between the heat-sealing jaws 14 and 15, so that they are heat-sealed to the netting in order to strengthen the package and provide regions for applying lettering for several purposes. In particular, Figure 6 illustrates a package in which the jaws form three heat-sealing lines: the line 62 closes the bottom of the overlying bag and the other two lines 63 and 64 delimit a band in which slots 65 which form a handle are formed by punching. Figure 7 illustrates an embodiment in which the bands 56, 57 are removed from the reels 58, 59 by means of advancement units 66, 67. Figure 8 is a view of a further embodiment in which instead of the inner tube there are two rings 68 and 69 which are accommodated in internal grooves 70, 71 of the outer tube 33, so as to provide effective retention by friction on the tubular netting 42, which is guided between the rings and the outer tube. In this embodiment, the opening 72 for inserting the products is formed between the rings 68, 69.
Still a further embodiment of the present invention, shown in Figures 9 and 10, replaces the outer tube 33 with multiple pairs of rollers 73, 74, 75 which retain the netting 42 against the faces of the inner tube 40.
The pairs of rollers 73-75 cantilever out from angular elements 76 which are fixed to the plates 20, 21 so that the rollers 73-75 are tangent to the faces of the inner tube 40. Conveniently, the pairs of rollers 73, 74 are arranged above and below the rollers 24, 25, while the pairs of rollers 75 are substantially at the same level as the rollers 24, 25.
As shown in Figure 11, the above-described apparatus can be provided with two mutually aligned stems 77, 78 which are actuated by respective jacks 79, 80 which are mounted on a platform 81 arranged below the frame 10. The stems 77, 78 are actuated in mutual opposition between a position for the free passage of the netting 42 and a position for engaging the netting 42, so as to prevent the slit 54a from descending due to the weight of the products introduced in the bag S.
Optionally, in order to prevent the slit 54a from descending below the heat-sealing line 63, a relative movement is performed between the plate 81 and the frame 10 so as to arrange the slit 54a between the heat- sealing lines 63, 64.
The disclosures in Italian Patent Application No. BO99A000260 from which this application claims priority are incorporated herein by reference.
Where technical features mentioned in any claim are followed by reference signs, those 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.

Claims

An apparatus for producing packages of horticultural products with tubular netting (42) which is unwound continuously from a reel, said apparatus comprising a frame (1), a tube (40) which is vertically suspended from said frame and inside said netting (42), said tube (40) having a lateral opening (47, 72) for loading the products which is aligned with the outlet of a product feeder (37), a cutting device (50) which is suitable to produce a slit (54a) in said netting in order to allow to load products inside said tube (40) through said slit (54a) and said opening (47, 72), characterized in that it comprises means (24-27, 30, 31, 48, 49) for controlling the sliding of said netting (42) on said tube (40) by an extent which defines a bag (S) for containing the products and means (14, 15) for closing said tubular netting (42) below said tube (40) according to two stacked closures (62, 63, 64), an upper closure (62) forming the bottom of said bag (S) and a lower closure (63, 64) closing the previously formed bag, means (14a, 15a) being further provided for cutting said netting (42) between said upper and lower closures (62 and 63, 64).
The apparatus according to claim 1, characterized in that said means for controlling the sliding of the netting (42) comprise at least two units for advancing the netting which are arranged in opposite positions of said tube (40), each unit comprising two stacked outer rollers (24-27) which are mounted to the side of said tube (40), a belt (30, 31) which winds around said pair of rollers, means (28, 29) for actuating said pair of rollers, at least one inner roller (48, 49) which is mounted on said tube, said rollers (24-27, 48, 49) being arranged at facing openings (45, 46) which are formed in said tube (40) so that the inner roller (48, 49) engages the belt (30, 31) between the outer rollers (24-27), said tubular netting (42) being guided between said belt (30, 31) and said inner roller (48, 49).
The apparatus according to claim 2, characterized in that said tube (40) is arranged inside an outer tube (33) which is fixed to said framework (1) and forms with it a gap (41) through which said netting (42) is guided, said outer tube being provided with openings (32, 35) which are engaged by said rollers (24-27, 48, 49) and said belts (30, 31).
The apparatus according to one of claims 1 to 3, characterized in that said tube (40) protrudes upward with an ogive-shaped point (44) which forms, with said tube, a step (43) for resting on said framework.
The apparatus according to claim 1, characterized in that said means for controlling the sliding of the netting (42) are constituted by two rings (68, 69) accommodated in slots (70, 71) of said tube which are formed above and below said product loading opening (72), said rings forming passages for said tubular netting in said slots.
The apparatus according to claim 1, characterized in that said closure means comprise two heat-sealing jaws (14, 15) and cutting blades (14a, 15a), said jaws being actuated between a spaced position and a mutually adjacent position at which said jaws (14, 15) form two stacked heat-sealed regions (62, 63, 64) for closing said tubular netting guided between them, while said blades (14, 15) sever said tubular netting (42) between said heat-sealed regions.
The apparatus according to claim 6, characterized in that said heat-sealing jaws (14, 15) and said blades (14a, 15a) are mounted on a frame (10) which can be adjusted vertically between a raised position for clamping said bag and a lowered position for spacing said jaws from said tubular net.
The apparatus according to claim 7, characterized in that said frame (10) is adjustable by virtue of means which comprise a plurality of sprocket wheels (8) which are supported rotatably on said frame and are engaged on respective threaded rods (6, 7) which are fixed vertically on the framework (1), a chain (9) being wound on said sprocket wheels and being actuated by a gearmotor (11) which is mounted on said frame.
The apparatus according to claim 8, characterized in that said outer rollers (24-27) of each unit are mounted on guides (18, 19), means being provided in order to adjust their position with respect to said tube (40).
The apparatus according to claim 9, characterized in that there are rollers (73-75) which are supported on said plates (20, 21) and tangentially engage said tube so as to clamp said netting (42) against said tube (40).
The apparatus according to claim 6, characterized in that stems (77, 78) are arranged under said frame (10) and are actuated by actuators (79, 80) in order to engage in said netting and raise said bag so that said slit (54a) arranges itself between said heat-sealing jaws (14, 15).