CZ2002677A3 - Plastic sheet with shaped pockets along its sides for weight insertion - Google Patents

Abstract

The invention refers to a plastic sheet for agricultural use (ground covering of any linear cultivation or any linear cultivation under low tunnels). For the firm fixing of plastic sheet (1) on a cultivation line, complex shaped pockets (9, 10) exist in which weight is inserted during its use on the field. The complex shaped pockets (9, 10) are formed by a complex shaped welding of two superimposed parts of the plastic sheet (1) along its sides. The complex shaped pockets (9, 10) along the two sides of the sheet (1) comprise two series of pockets of which one (10) can facilitate water or and the other (9) can facilitate soil. The advantage of this pattern is that the farmer can fix the plastic sheet (1) on the low tunnel or on the characteristic dyke of the asparagus cultivation, by either using soil or water or even both of the above.

Description

Plastic foil with shaped pockets along its sides to fill loads

Technical field

The invention relates to a plastic film for agricultural use (for covering the soil in any row cultivation or any cultivation under low tunnels). In order to firmly secure the plastic film to the cultivated row, there are associated molded pockets into which the load is filled when used in the field. The composite shaped pockets are formed by complex, shaped welding of superposed parts of the plastic film along its sides. The composite shaped pockets along the two sides of the film include two rows of pockets, one row facilitating the water filling and the other the soil filling. The advantage of this pattern is that the farmer can attach the plastic film to the low tunnel or to the characteristic asparagus growth level, either by using soil or water, or even both of these ballast materials.

BACKGROUND OF THE INVENTION

Plastic films used to cover the soil or in any cultivation under low tunnels can be divided into two categories, depending on their laying and their use:

• 9

2A (completed sheet)

(a) Traditional plastic films which, when used on the cultivated row, are fixed by placing the soil, manually or mechanically, on the surface of the film along its two sides. The production process of these films is quite simple, as is their laying on the field. The main drawback of this type of plastic film is that it interferes with carrying out the desired cultivation procedures on the cultivated row, making their use unsuitable for any linear cultivation (eg asparagus).

b) Foils that allow access to the cultivated row, which are more complex and have pockets along their two sides to fill the loads that can secure the foil to the cultivated row. The only category that has been widely adopted is that in which soil is used as a load (it is plentiful in the field and does not entail any additional costs). There are other categories, such as those using water (which is also sufficient and does not entail any additional cost). However, farmers are cautious about using water due to the fact that any damage that occurs on their pockets leads to water leakage and therefore these foils are characterized as inappropriate.

Several other solutions have been used, such as inserting ropes along the tubes formed at the sides of the film, or binding the plastic film (several methods have been adopted) at regular intervals to achieve its firm fixation. These solutions were used only at the experimental level.

WO-A-98,30082 (A. Daios) discloses an invention comprising a plastic sheet used for soil covering produced by extrusion from a flat or circular die head used for cultivating with soil covering or for ftftft ftftftft ftft ftft ft ftftft ftft ftft ftft

2B (completed leaf) cultivation in shallow ditches. To keep the foil securely on the ground, it carries repeating, separate pockets of water on both sides. The water flows into the pockets through the feed tubes and provides a load for rigidly holding the film to the shallow ditch frame and the like. However, it has been discovered that this plastic foil (pockets or filling tube) can be perforated, which is often the case when it is not used properly and carefully. Bearing in mind that this foil is intended to be reused for years, it is clear that over time the possibility of misuse increases.

US-A-5,158,395 (D. Holmberg) discloses a system for controlling the erosion of beaches and dunes of a backward receding coastline, including placing a large permeable mat with load pockets circumferentially and attached to the mat at the bottom of the water body so that at least a portion of this mat extends to a position where the current has a rate sufficient to erode the bottom, and stabilizers are below the water surface. These stabilizers are tubular elements filled with cementitious material, while the loaded pockets are filled with beach sand. This structure is absolutely different in its function and cannot be used in agriculture. It is only used on coasts and beaches, ie on receding sandy surfaces that are lashed by tides and waves to prevent erosion, undermining of shores, the creation of artificial sand barriers, etc. soil, because their shape and function is different.

Existing solutions, while allowing access to linear cultivation (eg asparagus, which is grown on artificial levels), have several drawbacks. Some of them will be briefly discussed here:

• «• ·

• ·

a) They cannot be easily reused. This is an important disadvantage when considering the relatively high cost of these films and the resulting environmental protection issues (recycling).

(b) Costs of own use if soil is used.

(c) Uncertainty in the use of water.

(d) The fact that the above solutions are not widely accepted, leading the plastic film manufacturer to have two products at its disposal.

e) The capacity of the pockets is based on the maximum wind speed, which is not necessary in most cases.

It is clear from the above description that both solutions comprising either the use of soil or water have several advantages, but at the same time they are disadvantageous in assessing themselves.

The complex problems of conventional access enabling plastic foils and soil covering methods are solved by the present invention of plastic foils with associated, shaped pockets to load, with an innovative solution.

SUMMARY OF THE INVENTION

The plastic film has two rows of different pockets on both sides, instead of one. One is filled with soil while the other is filled with water.

This solution combines the advantages of pockets with both water and soil. In addition, it is a solution that combines the ease of use of water, the easily distributed load due to its fluidity, and assuring the user of an alternative solution in case the water pockets are damaged. Obviously, the present invention automatically solves all of the above problems.

The end-user may have a plastic film that can be used in four different ways:

• ·

a) Filling with soil only pockets made for filling with soil (water pockets remain empty). This solution has low material costs but high labor costs and requires careful filling of pockets along the entire length.

b) Filling only pockets made for filling with water (soil pockets remain empty). This solution significantly reduces labor costs, but requires the use of special equipment to fill pockets with water.

c) Filling pockets with both water and soil. This solution is recommended in areas with prevailing wind conditions.

d) Filling several parts of the foil length with water and several others with soil. This solution is mainly used when plastic foil has been used for more than one year when several pockets have been damaged.

Several combinations can be adopted to meet the requirements of the end user, and moreover, it simplifies the production of the plastic film, since only one type of plastic film is produced for all possible applications.

A different possibility arises when the plastic film has two rows of pockets for filling loads of the same type (eg two rows of soil pockets on its side). This solution is best suited for users who support one of the solutions (either water or soil only) and intend to use the film for more than one year. Thus, if there are two rows of consecutive pockets, one of them can be used in the first year and can be destroyed when emptying the field to empty the contents from the pockets. The remaining row of pockets may be used in the second year. The same applies to solutions with water pockets.

The durability of the plastic film is ensured by the use of raw materials that exhibit exceptional tear and puncture resistance. Thus, polyolefins or combinations of polyolefins (LLDPE, LDPE, mLLDPE, EVA, PP) can be used as raw materials. In addition, additives can be mixed with the raw material to achieve the desired properties (color, deterioration, thermal properties, etc.).

The combination of the durability of the plastic film and the existence of two different types of pockets along the sides of the film provides the possibility of a service life longer than one year. The farmer may choose to use water pockets in the first year and soil pockets in the next year. In addition, there is the possibility of using water pockets - since they can be easily emptied if needed (due to their shaped shape) - for more than one year and thus extend the life of the film.

In addition, both solutions can be used simultaneously in areas with prevailing wind conditions, by self-doubling the load to be filled. This indirectly provides an opportunity to design (design) the plastic sheet in such a way as to withstand the most extreme wind conditions, and at the same time each pocket can be designed to have a volume sufficient for milder weather conditions.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described by reference to the following drawings, in which:

Giant. 1 - a method of manufacturing a plastic film with associated molded pockets for filling loads along its sides (manufactured from a flattened tube).

Giant. 2 - a second method of manufacturing a plastic film with associated molded pockets for filling loads along its sides (manufactured from a flattened tube).

Giant. 3 - a third method of manufacturing a plastic film with associated molded pockets for filling loads along its sides (manufactured from a single film having folded portions along its sides).

Giant. 4 is a detailed view of a method of forming associated molded pockets for loading loads.

Giant. 5 is a detail of a second method of forming the associated molded plastic film pockets.

Giant. 6 - detail of the method of filling the row of pockets (10) into water. On the supply tube (11) there are openings (14) - transverse or angled - allowing filling of the water pockets.

Giant. 7 - detail of a method of filling a row of water pockets by means of an un-welded portion at the bottom of each pocket (15) onto the soil through which the supply tube (16) is inserted.

Giant. 8 - detail of the method of filling a row of water pockets having a self-closing valve or a manually set valve (17).

Giant. 9 - plastic foil with associated shaped pockets for filling loads along its sides (2), used in cultivation under low tunnels (18).

Giant. 10 - plastic foil with associated shaped pockets for filling the loads along its sides (2), applied to the plane (20) in asparagus growing.

DETAILED DESCRIPTION OF THE INVENTION

A method for producing a film with associated shaped pockets for loading loads is described below.

The plastic film is produced by extrusion or coextrusion from a circular or flat mold and has a width A of up to 4 m, preferably 1 to 2 m, and a thickness of up to 200 µm.

The plastic film may have:

a) the form of the flattened tube 1 (Figs. 1 and 2) of the flattened portion A and the circumference 2A.

·····························

b) in the form of a single film 2 (Figs. 3 to 10) having staggered portions along two sides 3 with a width of up to 25 cm and preferably 17 cm.

On two sides along the entire length of the film, the superimposed parts are welded (which either exist as folds or flattened tubes) by combining the welds in such a way that a composite shaped pocket for filling the loads is formed. This pocket contains:

(a) a series of consecutive load pockets for use with soil; (b) a series of consecutive load pockets for use with water.

Such a combination of welding could arise from:

(a) a linear, continuous welding parallel to the length of the plastic film and at a distance b1 up to 15 cm, preferably 7 cm, from the edge 4. (b) a linear, partial welding 5 with a length L3 having a recurrent length (interval) L1; parallel to the length of the plastic film and at a distance b2 up to 20 cm, preferably 15 cm, from the edge, (c) repeated, molded welding 7 of the repetitive length L2 and of any geometric shape (e.g. and ends at a minimum distance of 3 cm from the linear welding 6, (d) repeated, transverse or beveled welding 8 with a repetitive length L1 starting from the continuous weld 6 and preferably ends at the center of each sub-weld 5.

this ·· to *

The volume created in this way between the partial welding 5 and the linear welding 6 and the two successive transverse welds 8 is a pocket 9 for filling the loads for use with the soil. The load is inserted through the unsealed portion between the two parts 12a of the partial linear welding 5 and its length is d = L1-L3.

Each water pocket 10 is formed between the edge 4 and the molded welding 7 of a repetitive length L2. The distance between two consecutive welds 9 is a passage 13 through which water flows into each pocket through a parallel tubular guide with a variable cross-sectional area.

This pipe is formed between continuous welding 6 and repeated molded welding 7, and has a diameter of at least 2 cm (over the entire circular section).

In this way, two rows of pockets are formed. On the inner part (regarded as the reference centerline along the plastic film), successive pockets of repeating length L1 (preferably greater than 1 m) are formed to facilitate the use of soil 9. On the outer part (considered as the reference center axis along the plastic) the consecutive pockets of repeating length L2 are formed to facilitate the use of water 10. The tubing 11 is positioned between two rows of pockets. For simplicity, the repeating lengths of the structures L1 and L2 could be the same.

The composite pattern of the pockets for loading the loads is preferably the same on both sides along the film.

Yet another method of making this film (Fig. 5 - detail) is by molding on the inner portion of a single film or flattened tube of water pockets 10, and on the outside of the soil pockets (considering the reference centerline along the plastic film). In this case, welding is formed 7 ····

between two linear (6a, 6b), continuous and parallel welds. And therefore:

and) One connected and linear welding 6a by could be in distance b2 to up to 20 cm, preferably 15 Dec cm from edge 4. (b) Second connected and linear welding by could be in distances up to to 15 cm and preferably 8 cm cm from edges 4. C) Every repeatedly molded welding 7 by had come out

from the second continuous welding 6b, terminating at a distance of not less than 3 cm from the first continuous welding, and should have a repeating length L2.

d) The successive transverse welding should have a repeating length L1 and start from the edge 4 ending in the second continuous welding 6b.

It is clear that in the case of the soil pockets 9 (which are formed between the second continuous welding 6b, the rim 4 and the two transverse welds Q), the load filling opening 12b should be formed. This opening is formed in the production of the film by dividing the film at a regular distance L2. These slots should be folded and should have a length d - preferably they should be located half the length of each soil pocket, very close to the second linear welding 6b.

It is clear that each of the above methods of manufacturing the invention could be formed by only one complex welding having a repetitive length L1 and comprising portions of linear and parallel welding 6, molded welding 7 and transverse welding 8.

Obviously, the present invention provides several possibilities of combined welding so that pockets of any shape and use can be formed along the plastic film. In this way they could have pockets for soil and pockets for water

0 · «0000 any geometric or natural shape (eg angled parallelepiped, oval, shaped shape, etc.).

Some combinations are as follows:

(a) Soil / soil pockets. Linear continuous welding is associated with partial welding, repeating transverse welding with repeating length L1 and repeating slots of repeating length L1 with length (d).

b) Water / water pockets. This is the most complex case requiring two continuous welds parallel to the foil length and two rows of formed welds. One of the formed welds should be placed between the edge and one linear welding and the other between the linear welds.

It is clear that the length of these plastic sheets used limits the supply of water to the entire length of the sheet (1 or 2).

It is common practice that the length of the cultivated line exceeds 300 m, while the tubular duct 11, with a thickness of 0.005-0.2 mm, would not withstand the water pressure required to fill 100 m of plastic film. For this reason, water should be supplied through special openings arranged regularly to supply water to the tubing. These openings could be:

a) a transverse or tapered slot 14 along the tubular guide. There should also be a weld in such a way that it prevents any water leakage from the adjacent pocket, while this slot provides the desired opening for filling the next pocket (Fig. 9),

b) a small non-welded part in the soil pocket to allow access to the tubing (Fig. 7),

c) a self-closing or manually adjusted valve located at the bottom of the soil pocket to allow access to the tubing (Fig. 8).

ΒΒΒΒ

ΒΒ ΒΒΒΒ

ΒΒ «• · β • · Β •

Β · ΒΒΒΒ

Β · Β ·· ·

To protect the soil pockets 9 from excessive rainwater, there should be a small opening just below the load opening (12a, 12b) to allow any trapped water to escape.

The plastic film with the folded shaped pockets along its sides 1 is wound in rolls during its production, preferably up to 1000 m, and could be absolutely symmetrical, considering the central axis as a reference.

When applying plastic film to a field, a field farmer could use it in three ways:

a) Filling the pockets 9 with soil. Each pocket is filled individually. The water pockets 10 remain empty.

b) Filling the water pockets 10. The plastic film having 1 or 2 associated molded load pockets along its sides is filled with water from one or two ends or from the supply openings 14, 15 or 16. The soil pockets 9 remain empty.

c) Filling the pockets with both water and earth. In this case a combination of a) and b) is adopted. This is recommended for areas where wind conditions prevail.

For the end user, the plastic film with associated molded pockets to fill the loads along its sides 1 or 2 represents a step worthy of confidence in ensuring the use of water due to the fact that the user has an alternative use of soil.

Claims (8)

PATENT CLAIMS (new claims) 1. Plastic sheet for covering soil, with associated molded pockets for filling loads along its sides, made of tear-resistant and leaky-resistant material such as LLDPE, LDPE, PP, EVA, etc., or combinations thereof, any color having width / A (up to 4 m and thickness up to 200 µm), the plastic film may be in the form of a flattened tube (1) or in the form of a single film (2) having folded parts along its sides (3); characterized in that it has along each side (3) and arranged one after the other: a) a series of consecutive pockets (9) for loading loads, for use with soil, and length (LI), b) a series of consecutive load pockets (10) for use with water of any shape and length (L2) so that the film can be used either as filled with soil or filled with water. Plastic foil with associated molded pockets for filling loads along its sides, according to claim 1, characterized in that all the pockets are formed on the plastic foil by complex welding of two superposed parts along the sides of the foil. Plastic film with associated shaped pockets for filling loads along its sides, according to claims 1 and 2, characterized in that the complex welding of two superposed parts on its sides is a combination of: a) continuous, linear welding (6), parallel to its length at a distance (b1) of up to 15 cm, preferably 8 cm, from the edge (4), b) repeated, partial welding (5) with a repeating length (L1), parallel to its length at a distance (b2) of up to 20 cm, preferably 15 cm, from the edge (4), c) repeated, molded welding (7) with repeating length (L2) and of any geometric and natural shape starting from the edge (4) and ending at a minimum distance of 3 cm from continuous linear welding (6), d) repeating transverse or bevel welding (8) with a repetitive length (L1) starting from continuous linear welding and preferably terminating at the midpoint of each discontinuous welding (5). Plastic film with associated shaped pockets for filling loads along its sides, according to claims 1 and 2, characterized in that the complex welding of two superposed parts on its sides is a combination of: a) linear, continuous welding (6a), parallel to its length at a distance (b2) up to 20 cm, preferably 15 cm, from the edge (4), b) linear, continuous welding (6b), parallel to its length at a distance (b1) of up to 15 cm, preferably 8 cm, from the edge (4), c) repeated, molded welding (7) of repeating length (L2) of any geometric or natural shape starting from the second continuous linear welding (6b) and ending at a minimum distance of 3 cm from the first continuous linear welding (6a), d) repeated transverse or angled welding (8) with a repetitive length (L1) starting from the edge (4) ending in a second linear welding (6b); and has successive slits (12b) of repeating length (L1), with length (d), parallel to the plastic film and very close to continuous linear welding (6b), and preferably at a midpoint between two successive transverse or beveled welds / 8 /. Plastic foil with associated shaped pockets for filling loads along its sides, according to claims 1 and 2, characterized in that the complex welding of two superposed parts along its sides is a combination of: and) continuous, linear welding / 6a /, parallel with hers length in the distance / b2 / up to 20 cm, preferably 15 cm, from margins / 4 /, (b) linear, continuous welding / 6b /, parallel with hers length in the distance / bl / do 15 cm, preferably 8 cm, from margins / 4 /, c) repeated, molded welding (7) with repeating length (L2), of any geometric or natural shape starting from the edge (4) and ending at a minimum distance of 3 cm from the first continuous linear welding (6a), d) repeating transverse or beveled welding (8), each starting from a second continuous, linear welding (6b) and ending in a first linear, continuous welding (6a); and has successive slits (12b) of repeating length (L1), with length (d), parallel to the plastic film and very close to the continuous, linear welding (6b) and preferably at a midpoint between two transverse or beveled welds (8) /. fl · «· · · · · · · Plastic foil with associated shaped pockets for filling loads along its sides, according to claims 1 to 5, characterized in that the repeating length L1 is equal to the repeating length L2. Plastic sheet with associated molded pockets for filling loads along its sides, according to claims 1 and 2, characterized in that the complex welding of two superposed parts on its side is formed by successive welding of a composite molded welding mold, the welding of which forms one or more soil pockets (9) of any shape and one or more water pockets (10) of any shape. Plastic foil with composite shaped pockets for filling loads along its sides, according to claims 1 to 7, characterized in that at regular distances up to 100 m opening points are provided for entering water into successive water pockets, which may be formed in several ways, such as: a) by means of slots (14) which are perpendicular or inclined to the water pockets, b) leaving one soil pocket, which in this case will not be used for soil, in conjunction with the water pockets through the non-welded portion (15), c) by inserting a self-closing or manually adjusted valve (17) into a soil pocket, which in this case will not be used for soil, by being connected to the water pockets; or (d) any combination of holes.