WO2019207175A1

WO2019207175A1 - Machine for filling bags with bulk goods and corresponding filling method

Info

Publication number: WO2019207175A1
Application number: PCT/ES2018/070323
Authority: WO
Inventors: Juan José González Toledano; Xavier Arderiu Cabau
Original assignee: Técnicas Mecánicas Ilerdenses, S.L.
Priority date: 2018-04-23
Filing date: 2018-04-23
Publication date: 2019-10-31

Abstract

Machine (1) for filling bags (100) with bulk goods (104) and corresponding filling method. The machine comprises a first station (2) with filling means (10) for filling a bag (100) and first mechanical compression means (12) arranged in such a way in relation to the filling means (10) that they compress the goods (104) as the bag (100) is filled with the bulk goods (104). The machine also comprises a second station (4), arranged downstream of the first station (2), with first sealing means (14) for sealing the filling opening of the bag (100). The machine is characterised in that the second station (4) comprises second compression means (16) and also in that it comprises a third station (6), arranged downstream of the second station (4), comprising second sealing means (18) for sealing the filling opening (102) of the bag (100). The invention also proposes a sealing method using the machine.

Description

MACHINE TO FILL SACKS WITH A BULK PRODUCT AND CORRESPONDING FILLING PROCEDURE DESCRIPTION

Field of the Invention

The invention relates to a machine for filling bags with a bulk product comprising: a first station comprising filling means for filling a bag and first means of mechanical compaction, said first means of compaction being arranged with respect to said means for filling said product as said sack is filled with bulk product, a second station, following said first station, which comprises first sealing means for sealing the filling mouth of said sack.

Also, the invention also relates to a filling process that is performed on the machine according to the invention.

State of the art

Machines for filling bags with bulk products are known, both in pre-formed bag filling machines, and in forming, filling and sealing machines that form their own bag and are known in the art for their English acronym FFS (by form , fill and seal). To fill the bags it is usual to take advantage of the effect of gravity, so that the product falls by its own weight centrally inside the bag. When falling into the bag, the product is not completely compacted and therefore occupies a volume greater than optimal. This has the disadvantage that it would require a larger bag than is strictly necessary. In order to solve this problem, it is known to have compaction means at the stage of filling the bag. The compaction means, either by tapping or by vibration, reduce the volume occupied by the bulk material.

Despite having the compaction stage, bulk bagging in conventional bagging machines presents an additional problem. The level of compaction required depends on the granulometric characteristics of the product, and its geometry and dimensions. In particular, the slope angle of the product is relevant, that is, the angle that forms a bulk product mound (similar to a cone), between the side wall of the mound and the horizontal wall of the base, when the product It stabilizes by itself. A reduced slope angle implies that the product has a favorable compaction capacity, while a large slope angle implies that the compaction capacity is unfavorable. If the product falls free and therefore forms a reduced angle, the bag is better filled. On the contrary, a large slope angle implies a lower filling level. In this context, it should be noted that, in the invention, a bulk product is understood as a product whose grain size is equal to or greater than 50 microns and preferably equal to or greater than 100 microns. Bulk products range from coarse powder to granular products. In addition, the particles have different shapes, such as spherical ball-like shapes or shapes that, without being strictly spherical, are more or less rounded. Alternatively, the particles may have irregular shapes with sharp edges, such as small cylinders, polyhedra or parallelepipeds. An example, not limiting, of this type of product, is plastic pellets. Figures 1 and 2 show examples of the geometry of two types of pellets.

As can be seen in Figure 1, a plastic pellet of polyamide, polyethylene or similar is shown, with rounded shapes and approximate dimensions of between 3 and 8 mm. The bulk product of Figure 1 has a first compaction capacity that is considered favorable. For example, if the compaction is done by tapping, it is sufficient that during the filling stage 1 punch is made in the bag to achieve optimum compaction As an alternative, in Figure 2, a plastic pellet is shown, such as the plastics described above, but in the shape of a cylinder with sharp edges and dimensions of the order of 3 and 8 mm. The bulk product of Figure 2 has a second compaction capacity less than the compaction capacity of the first product and which is unfavorable. Thus, in this second case, in order to achieve optimum compaction, it is necessary to perform between 8 and 12 strokes during the bag filling stage. This presents the problem, that when the filling stage is finished, compaction has not yet been achieved. Optimum bulk product. As a consequence the machine process slows down and therefore reduces its productive capacity.

Summary of the invention The purpose of the invention is to provide a machine for filling sacks with a bulk product of the type indicated at the beginning, which allows bagging at the maximum possible speed that allows the bulk product to be bagged and which, in addition, is as compact as possible This purpose is achieved by a machine of the type indicated at the beginning, characterized in that said second station also comprises second compacting means, and because said machine also comprises a third station, following said second station, which comprises second means of sealed to seal the filling mouth of said sack.

Indeed, this machine configuration is especially advantageous, since it offers great flexibility to adapt to the compaction characteristics of the bulk product that must be bagged, in combination with the product discharge speed.

In this way, in the case of products with a good compaction capacity, it can only be compacted in the first filling station during the filling stage. Then the full and compacted bag is moved to the second station, and finally the mouth of the bag is sealed.

On the other hand, in the case of products with poor compaction capacity, a first stage of compaction is carried out during the filling of the bag in the first station. Then, once the bag has been filled, it is transferred to the second station, and instead of sealing it, the bulk product is still compacted. In parallel, a second bag that can be filled has already been placed in the first station. Finally, after the compaction in the second station, the first bag can be passed to the third station to seal the filling mouth. When hitting the product multiple times, the slope is disassembled and the top of the bulk product becomes flatter. As a consequence, the filling is improved and the bulk density increases. This combination of two stages of compaction and two stages of sealing, in which the second stage of compaction overlaps with the first stage of sealing, provides great flexibility to the machine to pack products of very different granulometric characteristics and increases in a way Notorious the productive capacity of the same. The maximum capacity of a machine with a blow to fill or several blows to compact can drop 30% on a regular basis, more than 50% usually and in extreme cases if an extreme compaction is required approximately 80%. Thus, the possibility of carrying out a second stage of compaction minimizes the disadvantages of tapping, since while in the second season it is compacted, in the first station the next bag is already being filled.

Furthermore, the invention encompasses a series of preferred features that are the subject of the dependent claims and whose usefulness will be highlighted later in the detailed description of an embodiment of the invention.

In an advantageous embodiment of the machine, said first and second mechanical compaction means comprise a tapping element. He Mechanical tapping simplifies the design of the machine and reduces the need for maintenance and cleaning that other systems have, such as aspiration.

In order to reduce mechanical elements in the machine, in another embodiment, the tapping element is a conveyor belt disposed inferiorly to said filling station to support the base of said sack and swiveling mounted around an axis, said belt being reciprocating conveyor to hit the base of said sack. Thus, two functions can be merged into the same station. In addition, the lower tapping takes advantage of the effect of gravity and is more efficient.

In another embodiment that aims to reduce the need for manipulation by the operator, said third station comprises a conveyor belt to evacuate the sacks of said machine.

In another embodiment that aims to increase the compaction speed of bulk products with poor compaction and with smaller particle dimensions, said second station comprises suction means arranged superiorly to be inserted into said sack. In a preferred embodiment, the machine comprises a fourth station, upstream of said first station comprising means for feeding sheet material and bag forming means. The bag forming means consist of bag forming devices known in the prior art FFS machines. Therefore, the person skilled in the art knows its structure.

The invention also relates to a process for filling bags with a bulk product with a machine according to the invention and offering great flexibility. Thus, the procedure is adapted to the bulk product that must be bagged. In a first alternative of the process if said bulk product has a first compaction capacity, said process comprises the steps of:

[a1] place a first bag in said first station,

[b1] fill and simultaneously compact said bulk product contained in said first bag,

[c1] when the filling of said bag ends, transporting said first bag to said second station,

[d1] seal the mouth of said first bag in said second station,

[e1] when the sealing of said first bag is finished, transporting said first bag to said third station, and

[f1] evacuate said first bag,

while if said bulk product comprises a second compaction capacity, said second compaction capacity being less than said first compaction capacity, said method comprises the steps of:

[a2] place a first bag in said first station,

[b2] fill and simultaneously compact said bulk product contained in said first bag,

[c2] when the filling of said bag is finished, transporting said first bag to said second station,

[d2] compacting said bulk product contained in said first bag of said second station,

[e2] when the compaction of said first bag ends, transport said first bag to said third station,

[f2] seal the mouth of said first sack of said third station, and

[g2] when the sealing of said first bag is finished, evacuate said first bag from said third station. Particularly preferably, said method comprises a forced cooling stage between said sealing stage and said evacuation stage. For this, especially preferably, said third station comprises forced cooling means arranged in the upper part of the machine, oriented towards the mouth of said bag.

Likewise, the invention also encompasses other detail features illustrated in the detailed description of an embodiment of the invention and in the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS Other advantages and features of the invention can be seen from the following description, in which, without any limitation, preferred embodiments of the invention are mentioned, mentioning the accompanying drawings. The figures show: Fig. 1, a very enlarged view of a first type of bulk product.

Fig. 2, a very enlarged view of a second type of bulk product.

Fig. 3, a perspective view of a machine according to the invention.

Fig. 4, a perspective view of the machine of Figure 1.

Fig. 5, a side view of the machine of figure 1.

Fig. 6, a schematic view of the principle of operation of the machine according to figure 1.

Fig. 7, a schematic view of a second machine according to the invention.

Detailed description of embodiments of the invention

Figures 3 to 6 show a first machine 1 for filling bags 100 with a bulk product according to the invention.

In this case it is an FFS machine, that is to say that machine 1 manufactures its own bags 100, without the need to feed preformed bags.

In order of relevance in the invention, it can be seen that the machine 1 has a first station 2 comprising filling means 10 for filling a bag 100 with product 104 in bulk. The filling means 10 is a hopper that has appropriate feeding systems known to the person skilled in the art. In addition, machine 1 can dose in any of the ways known in the art. Thus, to determine the amount of material by weight that is deposited inside the bag, any of the three usual forms is used: the measurement of net weight, gross weight or weight loss.

The first station 2 also has first mechanical compaction means 12. Preferably, the mechanical compaction is performed by vibration or by tapping. However, especially preferably the first means of compaction 12 are an element of tapping. In this case, the tapping element is a conveyor belt 26 disposed inferiorly to the hopper. In this way, the conveyor belt 26 supports the base of the bag 100. To perform the tapping, the conveyor belt is swiveled around an axis 28 and during filling it is actuated in a reciprocating manner to strike the base of said bag 100 as The bag 100 is filled with bulk product 104.

Following the first station 2, a second station 4 is provided, which at the top has first sealing means 14 as a sealing jaw to seal the filling mouth of said sack 100. In this same station, by the lower part of the machine 1 and below the bag 100, second compaction means 16 are provided which again consist of a conveyor belt 26 that can swing around the axis 28 to perform the tapping.

In a third station 6, arranged after the second station 4, the machine 1 has second sealing means 18 arranged by the upper part of the machine 1 to seal the filling mouth 102 of the bag 100. By the lower part of the machine 1, in the third station 6 a conveyor belt is provided to evacuate the finished bags 100 of the machine 1. Finally, in this embodiment, upstream of the first station 2, the machine 1 comprises feeding means 22 of sheet material and bag forming means 20 common in the FFS machines. The procedure according to the invention that allows to implement the described machine is explained below.

Thus, the machine 1 according to the invention can implement two forms of operation, adapting to the compaction capacity of the bulk product to be bagged.

In the first alternative, if the bulk product 104 has a first compaction capacity defined as favorable, a first bag 100 is placed in the first station 2 from the fourth bag forming station 100. The bag 100 is filled with product the product 104 contained in the first bag 100 is compacted with the hopper and simultaneously with the conveyor belt 26.

Then, when the filling phase ends, this first bag 100 is transported to the second station 4, while a second bag 100 is fed from the fourth station. In the second station, the mouth 102 of the first bag 100 is sealed, while in the first station 2 the second bag of product 104 is filled and compacted. Once this stage is finished, the first bag 100 is transported to the third station 6, and evacuates once the seal has been sufficiently cooled. Simultaneously, a third bag is placed in the first station 2, and the second bag is transported to the second station 4 to seal it. The procedure is repeated until the required production is finished.

The second alternative of the process is intended for those bulk products 104 that have a second compaction capacity that is smaller than the first compaction capacity. In this case, if the procedure were performed described in the previous paragraphs, with the products with an unfavorable compaction capacity, in the first station 2 the filling of the bag 100 would be finished and instead, it would not have yet been compacted. This leads to loss of bagging capacity.

To avoid this problem, the procedure also begins by feeding a preformed bag 100 that is placed in the first station 2.

The first bag 100 will be filled and simultaneously the bulk product contained in the first bag 100 is compacted by patting the base of the bag by the conveyor belt 26.

Then, when the filling phase ends, but the product 104 is not yet compacted, the first bag 100 is transported to the second station 4, and a second bag is placed in the first station 2.

Then, unlike the first alternative, the bulk product 104 is continued to be compacted in the second station 4, while in the first station 2 the second bag 100 is filled and the compaction begins.

After the compaction is completed in the second station 4 and the bag 100 is filled in the first station 2, with the product partially compacted, the first bag 100 is transported to the third station 6 and the second bag 100 to the second station. Also, a third bag 100 is placed in the first station 2.

Next, the mouth 102 of the first bag 100 of the third station 6 is sealed, while the second bag 100 is compacted in the second station 4 and the third bag 100 of the first station 2 is filled. Once the sealing is finished and correspondingly cooled, the first bag 100 of the third station 6 can be evacuated and the second and third bags transported to the next station, placing a fourth bag in the first station 2. Obviously, transport between stations is carried out taking into account the stage that requires more processing time. Usually, this stage is that of filling in the first station 2. Below are other embodiments of the machine 1 according to the invention that share a large part of the characteristics described in the preceding paragraphs. Therefore, from now on only the differentiating elements will be described, while for the common elements reference is made to the description of the first embodiment.

The first difference observable in the machine shown in Figure 7, is that it is not an FFS type machine, but that the bags 100 are already pre-formed. Therefore, in this case, the preformed bags 100 are removed from a warehouse 28 by means of a manipulator 30 which transfers them to the first station 2.

On the other hand, another relevant difference in this embodiment consists in that the second station 4 has suction means 24 arranged superiorly to be inserted in said bag 100 to assist in the compaction. In another embodiment, the suction means 24 could also be provided in the first station 2.

Finally, in this alternative embodiment, the conveyor belts 28 are not tiltable, but vibrate at a high frequency.

Obviously, the differences described here are also applicable to the machine of the first embodiment. As has been explained, the machine 1 according to the invention makes it possible to significantly increase the flexibility of the machine and, consequently, its productive capacity. In addition, thanks to the overlapping of functions in the second station, machine 1 is especially compact.

Claims

1.- Machine (1) for filling bags (100) with a bulk product (104) comprising:

[a] a first station (2) comprising filling means (10) for filling a sack (100) and first mechanical compaction means (12), said first compaction means (12) being arranged with respect to said means filling (10) to compact said product (104) as said sack (100) is filled with bulk product (104),

[c] a second station (4), following said first station (2), comprising first sealing means (14) for sealing the filling mouth of said sack (100), characterized in that

[d] said second station (4) also comprises second compacting means (16), and in which said machine also comprises

[e] a third station (6), following said second station (4), comprising second sealing means (18) for sealing the filling mouth (102) of said sack (100).

2. Machine (1) according to claim 1, characterized in that said first and second mechanical compaction means (12, 16) comprise a tapping element.

3. Machine (1) according to claim 2, characterized in that said tapping element is a conveyor belt disposed internally to said filling means to support the base of said sack (100) and swivel mounted around an axis, said being reciprocating conveyor belt to hit the base of said sack (100).

4. Machine (1) according to any of claims 1 to 3, characterized in that said third station (6) comprises a conveyor belt to evacuate the sacks (100) of said machine (1).

5. Machine (1) according to any of claims 1 to 4, characterized in that said second station (4) comprises suction means (24) arranged superiorly to be inserted in said sack (100).

6. Machine (1) according to any of claims 1 to 5, characterized in that it comprises a fourth station (8), upstream of said first station (2) comprising feeding means (22) of sheet material and about means of sack formation (20).

7. Procedure for filling bags (100) with a bulk product (104) with a machine (1) according to claims 1 to 6, characterized in that

If said bulk product (104) has a first compaction capacity, said process comprises the steps of:

[a1] place a first bag (100) in said first station (2),

[b1] filling and simultaneously compacting said product (104) in bulk contained in said first bag (100),

[c1] when the filling of said bag (100) ends, transporting said first bag (100) to said second station (4),

[d1] seal the mouth (102) of said first bag (100) in said second station (4),

[e1] when the sealing of said first bag (100) ends, transporting said first bag (100) to said third station (6), and

[f1] evacuate said first bag (100),

while if said bulk product (104) comprises a second compaction capacity, said second compaction capacity being less than said first compaction capacity, said method comprises the steps of:

[a2] place a first bag (100) in said first station (2),

[b2] filling and simultaneously compacting said product (104) in bulk contained in said first bag (100),

[c2] when the filling of said bag (100) ends, transporting said first bag (100) to said second station (4), [d2] compacting said bulk product (104) contained in said first bag (100) of said second station (4),

[e2] when the compaction of said first bag (100) ends, transport said first bag (100) to said third station (6),

[f2] seal the mouth (102) of said first bag (100) of said third station

(6), and

[g2] when the sealing of said first bag (100) ends, evacuate said first bag (100) from said third station (6).

8. Method according to claim 7, characterized in that it comprises a forced cooling stage between said sealing stage and said evacuation stage.