Classifications

• • E—FIXED CONSTRUCTIONS
  • E06—DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
  • E06B—FIXED OR MOVABLE CLOSURES FOR OPENINGS IN BUILDINGS, VEHICLES, FENCES OR LIKE ENCLOSURES IN GENERAL, e.g. DOORS, WINDOWS, BLINDS, GATES
  • E06B9/00—Screening or protective devices for wall or similar openings, with or without operating or securing mechanisms; Closures of similar construction
  • E06B9/52—Devices affording protection against insects, e.g. fly screens; Mesh windows for other purposes
• • A—HUMAN NECESSITIES
  • A45—HAND OR TRAVELLING ARTICLES
  • A45F—TRAVELLING OR CAMP EQUIPMENT: SACKS OR PACKS CARRIED ON THE BODY
  • A45F3/00—Travelling or camp articles; Sacks or packs carried on the body
  • A45F3/52—Nets affording protection against insects
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04B—KNITTING
  • D04B21/00—Warp knitting processes for the production of fabrics or articles not dependent on the use of particular machines; Fabrics or articles defined by such processes
  • D04B21/10—Open-work fabrics

Definitions

• the invention relates to a screen more particularly intended to prohibit the passage of insects to protect crops, whether vegetable or horticultural, including greenhouse crops or even field crops.
• insects have long been met with the ravages of insects, whether they be indigenous or from migrations arising from trade between continents. These insects attack some crops by developing diseases that partially or totally destroy them, affecting production yields or making products unfit for consumption.
• the nets available today are made by weaving using simple armor such as canvas or taffeta with a cross warp son and perpendicular weft.
• simple armor such as canvas or taffeta with a cross warp son and perpendicular weft.
• Such a net is for example described in WO03 / 074771.
• Mesh nets having fairly large openings typically of the order of 850 to 1,000 ⁇ m, or even smaller, of the order of 350 ⁇ m, are also known.
• the armor used in such nets define low rates of opening, typically of the order of 35 to 40%, providing certainly the mechanical barrier against insects, but on the other hand do not allow a good exchange of air and therefore opposing good aeration of crops.
• we must use relatively large diameter son so that the resulting texture has a good behavior over time and thus avoid a risk of slippage of the son network, likely to change the size openings and therefore affect the mechanical barrier against insects.
• the resulting net has a certain rigidity, likely to oppose the folding and unfolding whose nets are likely to be subject because of their positioning, especially at the level of the moving parts of the opening of the greenhouses.
• the object of the invention is to provide a screen, intended to oppose the ravages of insects, and implementing a net of a new type, freeing itself from these various disadvantages and in particular fulfilling the primary function that it is devolving, namely the realization of an insect barrier, while offering higher aeration rates to the nets of the prior art, and may also have a longer life.
• this insect screen consists of a net based on textile yarns made by knitting with knitted stitches on machine chain or Rachel.
• This technique therefore allows the implementation of very thin monofilaments, thus contributing to obtain a factor or opening rate greater than the nets of the prior art.
• the surface of the orifices defined by the stitches relative to the surface occupied by the strands becomes significantly larger.
• the supply of air and light, both constituting factors determining growth of crops, is greatly improved.
• the technology knitting jetted mesh makes it possible to vary the geometry of the orifices, also to lead to the definition of orifices of very small dimensions, more particularly adapted to the fight against specific insects also very small.
• the opening ratio defined as being the ratio of the surface of the orifices on the total surface of the net is greater than 50%.
• the net defines orifices of substantially square or rectangular shape obtained by knitting stitches with implementation of sectional weft son.
• the thread defines orifices of substantially hexagonal shape, obtained by knitting, but the weft son are variable jetty and not constant.
• Figure 1 is a schematic illustration of a net obtained by weaving in accordance with the prior art.
• Figure 2 is a schematic representation of a net obtained according to a first embodiment of the invention, defining rectangular shaped openings.
• Figures 3 is a view similar to Figure 2, wherein the holes are square.
• Figure 4 is a schematic representation of a net obtained according to a second embodiment of the invention, defining hexagonal shaped orifices.
• FIGS 5, 6, 7 and 8 illustrate the technology implemented according to the type and shape of the desired orifices.
• Figures 9 and 10 illustrate the positioning of the net according to the invention respectively at a greenhouse and at the opening of a greenhouse.
• Figure 11 is a schematic representation illustrating the embodiment of the attachment system according to the invention.
• Figure 1 shows an insect net of the prior art obtained by weaving. We denote by 100 the son of chains, and by 101 the weft son.
• this weave defines orifices 102 of surface S1 of substantially rectangular shape.
• the warp and weft threads 100, 101 are of relatively large dimensions so as not to affect the size of the orifices 102 and in particular their surface S1. Indeed, in the case where the son 100, 101 are too thin, it is observed that the network has no mechanical strength, the son sliding between them, so that the size of the orifices 102 is no longer preserved, This can lead to bigger holes, which are unsuitable for the insect barrier function. As a corollary, because of the use of large diameter wires, these tend to reduce the passage of air, affecting the climatic conditions of the crops to be protected by such a net.
• FIG. 2 shows a schematic representation of a first embodiment of the net according to the invention. This is achieved by the technique of jersey knitting discarded, such as for example implemented on trades type RACHEL marketed by the companies KARL MAYER or LIBA.
• This net comprises, according to this embodiment of the chain 204 mesh with weft son 205, in this case of sectional nature, as will be described later in more detail.
• This knitting defines orifices 202 of surface S1 '. It is noted that the ratio of the surface S1 'with respect to the surface S2' defined in said figure and corresponding to the sum of the surface S1 'of the orifice 202 and that occupied by the wires defining the orifice in question. is much larger than the ratio of said surfaces resulting from the net obtained by the conventional weaving technique of FIG.
• Sample I corresponds to a net whose openings have dimensions of 500 x 500 ⁇ m, more particularly adapted to the protection against various insects: aphids, flies, whiteflies ...;
• Samples II and III correspond to a net whose openings have dimensions of 250 x 730 ⁇ m, more particularly adapted to protection against Bemisia Tabachi;
• Samples IV and V correspond to a net, whose openings have dimensions of 290 x 320 ⁇ m, more particularly adapted to protection against thrips.
• the control net is a conventional woven with 0.20 / 0 threads, 22 mm and with a porosity (ratio between the surface of the holes and the surface unit) of the order of 38/40%.
• the measurements are made in the wind tunnel; we note the speed of the wind, its modification after the passage through the net as well as various factors which then make it possible to determine by calculation, the decreases of flow on the net itself and in its position of use, ie when placed on a greenhouse structure.
• the flow rate reduction values indicated thus correspond to data directly usable by the builders and horticulturists to determine their crop operating conditions.
• the invention makes it possible to define different types of geometry of opening by the implementation of the technology "discarded mesh”.
• FIGS. 5 to 8 illustrate the technology making it possible to obtain these different geometrical shapes.
• the technologies illustrated in FIGS. 5 and 6 make it possible to obtain threads, the orifices of which are of rectangular or square shape, the binding being obtained according to the technology of the stitched mesh.
• the reference Bl illustrates the chains which work on a single column of needles.
• the wire guide bar works in 00/22 armor.
• Thread B2 Illustrates a sectional weave working by means of a wire guide bar according to the 10/01 weave, the assembly having been shown for a fine gauge of twenty-eight needles per inch (25.40 mm)
• the distance e separating two adjacent chains corresponds to the space between two needles, the diameter of the wire being selected to determine the width of the orifices 202, 302 of the net. It is thus possible to obtain orifices of 500 ⁇ 500 ⁇ m. Such nets are advantageously used. the insect thrips, reducing the size of the side to 350 ⁇ m.
• FIG. 6 is a view similar to FIG. 5 but implementing a larger gauge, typically 22 needles per inch, and with a different ratio between the warp density and the weft density, so as to obtain a thread whose orifices are rectangular in shape, typically 250 ⁇ m wide for a length of 730 microns.
• FIG. 7 represents another type of binding, making it possible to obtain a thread whose orifices have dimensions of 700 .mu.m to 900 .mu.m on the side with a wire of 0.08 to 0.10 mm, and which can serve as a barrier against insects like aphids and some flies or whiteflies.
• the chains B1 are of the type previously described but working in a 10/10 armor.
• the threads B2 consist of a gill yarn and alternatively embroidering. particularity of a very great holding and dimensional stability.
• FIG. 8 makes it possible to obtain a thread, the orifices of which are of substantially hexagonal shape, making it possible to define a honeycomb structure.
• a net is advantageously used to prohibit the passage of particular insects, of the type mentioned above.
• This geometry has the advantage of not being directional and therefore of presenting a uniform isotropic behavior in all directions.
• the warp threads B1 work on two needle columns in contrast to the three previous embodiments.
• the working armor of the corresponding needles is 10/01/10/12/21/12.
• the weft yarns are variable jetty and not constant as for FIG.
• the net of the invention is likely to have both weathering and ultraviolet resistance characteristics to provide multi-year functionality.
• the constituent son is made of polyethylene or polypropylene, the base polymer receives an antioxidant.
• biodegradable nets to meet certain environmental type constraints for example.
• son of polyester, polyamide or polylactic acid for example.
• FIGS. 9 and 10 show examples of mounting the net according to the invention. It can conventionally close one of the 906 or the two lateral faces of access to a greenhouse 907. It can also be in the form of a lateral strip 908 extending along the entire length of the greenhouse, as shown in Figure 9, and intended to close the greenhouse 907 at this level against insects, but not against the passage of air.
• some greenhouses are provided with openings 1009, including glass greenhouses, to allow to vary the climatic conditions that prevail in the volume they define, such openings being hinged 1010 on the greenhouse. It is also desired to protect insects despite the use of such an opening, so that it is matched with a net 1011 according to the invention for, although allowing the passage of air , prohibit access to insects (see Figure 10). The net in question is then secured by any means to the respective edges of the fixed part and the movable part of the opening.
• systems 1012, 1013 for retracting the net towards the interior of the greenhouse are used when it is desired to close off the opening in question.
• traction is performed on said net by any means, and in particular a linkage system or a system of ropes secured to the inner face of the net, and more particularly to a reinforcing strip 1014, which can be reported by binding over the entire length of the net.
• FIG. 11 there are reported on said inner face additional technical threads 1110 (FIG. 11), suitable for creating loops 1111 at which the return means or the rods 1112 are secured.
• These loops 1111 are defined by the introduction of mechanically resistant technical yarns always by knitting, these yarns being bonded into zones 1113 with a specific bonding strong enough to form a sufficient link with the net, without the risk of tearing. use.
• loops are made during the manufacture of the net, and are distributed relatively uniformly and periodically along the net, and for example spaced every 30 cm.
• the net can be unfolded or folded at will, during the movements of the opening, with ease of retraction inside the greenhouse.
• loops or attachment zones are constituted by son, or of the same nature as that of the son constituting the net, or of different nature, and in particular larger diameter and more mechanically resistant.
• reinforcing son are thicker than the constituent son of the net itself, and having a specific resistance. They are separated from one another by a distance of between 1 cm and 20 cm depending on the importance of the desired reinforcement, said reinforcement son being reported directly on the net during the manufacture of the latter.

Landscapes

• Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Pest Control & Pesticides (AREA)
• Structural Engineering (AREA)
• Textile Engineering (AREA)
• Insects & Arthropods (AREA)
• Architecture (AREA)
• Civil Engineering (AREA)
• Catching Or Destruction (AREA)
• Protection Of Plants (AREA)
• Knitting Of Fabric (AREA)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

Country Status (6)

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Family Cites Families (5)

• 2006
  • 2006-10-31 FR FR0654680A patent/FR2907805B1/fr not_active Expired - Fee Related
• 2007
  • 2007-10-29 ES ES07866506T patent/ES2401302T3/es active Active
  • 2007-10-29 WO PCT/FR2007/052263 patent/WO2008053116A2/fr not_active Ceased
  • 2007-10-29 MX MX2009003110A patent/MX2009003110A/es active IP Right Grant
  • 2007-10-29 EP EP07866506A patent/EP2079341B1/de active Active
• 2009
  • 2009-03-26 IL IL197822A patent/IL197822A/en not_active IP Right Cessation

Non-Patent Citations (1)

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