The invention belongs to the field of mechanics with regard to anti- mosquito net systems that are used for horizontal door sliding.

According to the current state of the art, those systems mainly use pleated mosquito net, with pleated texture, so that the net can fold and unfold. The present invention refers to anti-mosquito systems with such pleated net.

These systems are like a frame, that has as its vertical sides two boxes: the restraint and the sliding one. The restraint box is fixed, screwed and stabilized on one of the vertical door frames, while at the same time one lateral fixed rail is screwed and fixed on the opposite vertical door frame. The sliding box is moving from the restraint box towards the fixed lateral guide and backwards, always in a parallel position to these two accessories. The pleated net is folded into its pleats, between the two vertical boxes, the fixed restraint box and the moving sliding one. The frame has two articulated guides, as its two horizontal sides, the upper and the lower. Those articulated guides are formerly used as guides in several applications (see for instance IGUS' DE 3806400, guides for electrical cables). The two articulated guides move inside two fixed horizontal guides, which are screwed when placed on the upper and the lower opening of the door frame.

According to today's state of the art, the anti-mosquito systems with a pleated net and articulated guides work in principle as follows: in most of the systems the articulated guides are vertical inside the restraint box and inside the sliding one. The net is folded into its pleats, between the two vertical boxes, the restraint and the sliding one. As the user pulls the sliding box and directs it towards the vertical lateral guide, which is screwed on the opposite vertical door frame, the two articulated guides, due to their joints, are retracted by articulation and get out of the upper and the lower opening of the restraint box and of the sliding box and from their vertical position take now an horizontal position at the upper and the lower door opening. At the same time, the pleated net is unfolded. When the user makes the opposite movement, that is to bring the sliding box back in its original position next to the restraint box, the two articulated guides, due to their joints, are retracted again by articulation and enter the restraint and the sliding box, one from their upper openings and the other from their lower openings, taking again a vertical position inside the two boxes. At the same time, the pleated net is folded in its pleats.

In all the systems of today's state of the art, the above mentioned working is aided by short ropes, which mostly work as follows:

All the short ropes have their one end fixed on the restraint box. They are unified in two rope groups of equal number, the upper and the lower group.

The short ropes crossing the middle of the upper part of the net, form the upper group. The ends of the ropes run horizontally through the net and then unify in one bundle, which is fixed on the upper end of the upper articulated guide.

The short ropes crossing the middle of the lower part of the net, form the lower group. The ends of the ropes cross horizontally over the net and then unify in one bundle, which is fixed on the lower end of the lower articulated guide.

When the user pulls the sliding box and directs it towards the vertical lateral guide, the pleated net is pulled along and gets unfolded, alongside the short ropes, which keep the net unfolded in its place. When the user moves the sliding box to the opposite way and directs it back towards the restraint box, the pleated net is folded in its pleats, alongside the short ropes.

In order to place anti-mosquito systems with articulated guides and a pleated net at an opening (door frame), the width and height measurements of the specific opening are required to be taken correctly. The restraint and the sliding boxes, as well as the lateral guide, are always ordered in the exact height of the specific openings. When the anti-mosquito systems are prepared, they are delivered set to be placed mounted as a folding closed frame. That is, the restraint box and the sliding box are in the specific measurements of the opening ordered for, the net is in its position between them and the two articulated guides (upper and lower) are placed inside the box (usually in the restraint box). In other words, it is a prepared frame which is screwed on the specific opening it was ordered for. The same applies of course to the vertical lateral guide which is also delivered in the specific height it was ordered for so as to be screwed on the opposite vertical door opening.

In order to place the system the restraint box is screwed on one of the vertical frames and the vertical lateral guide on the opposite vertical frame, that is in a parallel position to the restraint box. The sliding box is in parallel position and moves between the restraint box and the lateral guide.

The technical problems that today's above-described state of the art presents are the following:

If the frame's measurements are not taken properly, and more specifically the height measurements of the restraint box, the sliding box and the vertical lateral guide, the entire anti-mosquito system is useless, and thus the measurements must be retaken and a new system must be ordered from the outset. It is entirely replaced because, what regards the placement, the system is a unified technical element, a prepared frame of four sides, manufactured in the specific measurements of the order. The upper and the lower horizontal sides are pleated due to the articulated guides and do not create any problems, but the vertical lateral jambs, which regard the height of the opening, are of fixed and not variable length. The anti-mosquito system that was cut and mounted in wrong measurements is not repaired and there is not any .possibility to replace any of its accessories. If the height of the vertical lateral jamb and that of the two boxes were wrongly measured, then only a mistake in the order of ± 1 mm accepts an excuse.

The above mentioned technical problems are intended to be solved by EP 0549209, EP 1903175 and EP 0999335. However, none of them offers the possibility to rectify the measurements, in case they've been measured wrong, since they are complete products which are manufactured as assembled frames of fixed measurements. Cutting the frame afterwards would fully disassemble the system and thus make the product useless. A second technical problem that today's state of the art presents is that, when the mosquito net is folded and the two articulated sliding guides revert and enter the fixed restraint box, one from the upper opening and the other from the lower opening, the two guides slide (in some systems) one over the other or one inside the other, or (in some other systems) they slide inside metal skeletons, with a result to create huge and irritating noise, due to the fact that the one end of the articulated guide is bound with a short rope to the end of the other articulated guide inside the restraint box. The short rope pulls the guides in a direction out of a straight way. That opposite inclination, that the attraction from the short rope exerts on their ends, causes the guides' friction either between them or against metal skeletons and because of that it creates noise.

Finally, a third technical problem apart from the noise is that the two guides, when they meet each other and terminate, sometimes hook each other and thus they get blocked. In order to unblock them, the user has to pull the articulated guides out of the sliding box by using force. By a repeated blocking, the guides' ends are damaged and they need to be replaced.

The above mentioned technical problems are intended to be solved by EP 1653038 in which, contrary with the present invention, the two horizontal guides of the system, the upper and the lower, are not at all autonomous. Neither the upper guide nor the two terminal accessories can be detached from the restraint and sliding boxes without disassembling the entire system. If detached, the two restraint ropes will also get detached, which will consequently disassemble the lower guide, the lower terminals, held by the lower restraint rope and thus the entire system.

There are also solutions permitting the rectification of the wrong measurements by using the kit, as presented at the pending applications GR 20100100552 (EP11386006.8) and GR 20110100129 (PCT/GR2011/000016), functioning however in a different way than the present invention. More particularly, at the GR 20100100552 (EP1 1386006.8) in order to solve this technical problem, an additional accessory is being used. That is, the height regulator (no. 8 in the application), an accessory not needed at the present invention. At GR 20110100129 (PCT/GR2011/000016) two articulated guides are used (no. 3 and 4 in the application), the upper and the lower one, placed diagonally, whereas the present inventive idea needs for its application only one articulated guide at the lower part.

Finally, EP 2157274 A2 and EP 1653038 A2 also propose a kit solution. Nevertheless, these two solutions present significant differences in comparison with the present invention, since they use accessories not needed at the present one, such as a prop (no 36), a coil spring (no 34), the articulated guide is not fixed neither on the sliding nor on the restraint box (Drawings 4-7) (EP 2157274) etc., and also present a completely different ropes' pattern, in comparison with the present invention, using many springs (26) (EP 1653038 A2 Drawings 14-19).

The present invention solves the above mentioned technical problems as regards the wrong measurements that might be taken, the noise and the blocking of the guides and applies to the anti-mosquito systems that move horizontally and have a pleated net.

In brief, the invention does not use two articulated guides, like most of the systems of the current state of the art, but only one articulated guide at its lower part. Moreover, in the basic application of the inventive idea, the invention has both of the boxes to move freely at the user's will and open and close the net from the side of the leaf of the door frame that serves the user. That is, none of the boxes is stably screwed on the lateral door frame. The net opens and closes as much from the left as from the right vertical lateral door frame.

The invention presents great movement autonomy due to the fact that the net consists an autonomous detachable component together with the ropes, that enters sliding between the two boxes. Moreover there are two sets of ropes on the net, starting the one across one another. In the basic application of the inventive idea, the second set of the ropes circles the entire system and terminates at the same side the first one terminates. The fact that both of the ropes terminate at the same point of the articulated guide, gives great balance to the system.

Also, the present invention uses autonomous detachable ending parts, screwed on the system during placement. In another application of the same inventive idea, where the user does not wish to open the net from both sides, but only from the left or only from the right one, the box of the lateral door frame of the side that won't open and close, is screwed and fixed on the lateral vertical door frame. The second set of short ropes does not have to circle the entire system but terminates and fixes on the lateral guide, whereas the spare part of the rope can be cut and thrown away.

For the best fixing of the ropes, the user has the choice to use the special tension accessory of the short ropes, which offers a precise regulation of the ropes' volume of tension, so as to minimize the force needed from the user in order to unfold the net.

A first advantage of the present invention is that due to the kit function, it solves the technical problem created when the anti-mosquito net's order arrives from the factory in wrong measurements, bigger in height than the opening in which the system is about to be placed; a common problem.

Another advantage is the possibility to cover openings of any length. In particular, in big door frames, the user can use more than one systems, which will open and close from both vertical lateral door frames as mentioned above, but alongside this system the user can place at least one more and provide movement autonomy to every system.

The solution of that problem is maximised as the production factory can produce directly prepared pre-manufactured mosquito net systems (kit) in specific height categories of the two boxes and the lateral rail, for example "kit with boxes and rail height from 1900 to 2200 mm", "kit with height from 2201 to 2500 mm" and "kit with height from 2501 to 2800 mm".

Consequently, the placement of the systems is done very easily and quickly. Moreover, another advantage of the present system is the saving of time, offered by the autonomous kit, avoiding in that way the wait for the order of specific measurements to be delivered. Furthermore, the placement of the kit at the placement room is extremely quick and simple, since it only requires the cut of the system at the right length and the screw of the detachable caps. Another advantage is that since only one articulated guide is used, which comes in and out of the box in a completely vertical position, without reaching a second articulated guide and be hooked on it, the friction between the system's accessories is nullified and hence the noise created during the working. In that way, the system is extremely user friendly.

Another advantage is that the present system offers the possibility to replace the net separately in case of damage. A new assembled net with short ropes is produced separately and enters sliding between the two boxes from the upper side, where there are the detachable caps, without the need of replacement of the entire system.

As a consequence, the additional advantage is the efficacious reduction of the cost of production, which is very cost-effective for the user.

The 25 Drawings that accompany the description illustrate, in brief, the following:

Drawing 1 presents the net system with bilateral opening, with the pleated net fully unfolded, with two set of short ropes of equal number.

Drawing 2 presents the net system with bilateral opening at the left side of the opening, with the pleated net partly unfolded.

Drawing 3 presents the net system with bilateral opening at the right side of the opening, with the pleated net partly unfolded.

Drawing 4 presents the net system with bilateral opening, with the pleated net fully folded, and the system located at the middle of the opening.

Drawing 5 presents the net system with bilateral opening, with the pleated net fully folded, and the system located at the left side of the opening.

Drawing 6 presents two net systems with bilateral opening, with the pleated net fully unfolded, placed the one after the other.

Drawing 7 presents two net systems with bilateral opening, with the pleated net fully folded, each one located at random points of the opening.

Drawing 8 presents the accessory that regulates the ropes' volume of tension, in case a bundle of three short ropes is used (Figure 8a) and in case only one short rope is used (Figure 8b). Drawing 9 presents the first step of the placement of the net system with bilateral opening at the placement room. That is, the cut of the boxes, of the net and of the two lateral guides at their higher ends. At this step the bundle of the set of short ropes that circles the system, is below the minimum cutting point of the boxes. It also depicts the two upper caps of the two boxes and the two upper caps/pulleys of the two vertical fixed lateral guides.

Drawing 10 presents the second step of the placement of the net system with bilateral opening at the placement room, where the lower caps are screwed on the lower ends of the two boxes.

Drawing 1 1 presents the third step of the placement of the net system with bilateral opening at the placement room, where the bundle of the set of short ropes that circles the system, comes through the upper cap of the box that does not enclose the articulated guide, via pulley. Hereupon, the two upper caps are screwed on the upper ends of the two boxes. It also depicts the two lateral guides and their two upper caps/pulleys.

Drawing 12 presents the fourth step of the placement of the system with bilateral opening at the placement room, where the bundle of the set of short ropes that circles the system, comes through the two caps/pulleys of the two vertical fixed lateral guides. Subsequently, the bundle enters, via pulley, the box enclosing the articulated guide, comes down to the cap of the lower end of the box, where it comes up, via pulley, and fixes on the last protrusion of the articulated guide. The two lateral guides are also depicted.

Drawing 13 presents the fifth and last step of the placement of the system with bilateral opening at the placement room, where the two upper caps with the pulleys and the bundle of ropes are screwed, on the two upper ends of the two lateral guides. Finally, the ropes are tightened according to the width of the opening, either by hitch setting either by using the two accessories that regulate the ropes' volume of tension. Drawing 14 presents the net system with bilateral opening, with the pleated net fully unfolded, with two sets of short ropes of unequal number, the one set with two short ropes and the other with four. Every set starts from a different side of the net. The lower and the higher rope start from opposite sides.

Drawing 15 presents the net system with lower articulated guide with bilateral opening, with the pleated net fully unfolded, with two sets of short ropes of unequal number, the one set with one short rope and the other with five. Every set starts from a different side of the net. The lower and the higher rope start from opposite sides.

Drawing 16 presents the net system with lower articulated guide with bilateral opening, with the pleated net fully unfolded, with two sets of short ropes, each set consisting of one and only short rope. Every set starts from a different side of the net, the one from the highest possible point of the one side, the other from the lower possible point of the opposite side of the net.

Hereupon, the way of implementing the same inventive idea is presented, in case the user wishes to open the net only from the one side of the opening (unilateral opening), either the left or the right one, so the box of the side that won't open and close, can be screwed and fixed on the door frame, if the user wishes to do so. In this way of implementing the same inventive idea the second set of short ropes does not have to circle the entire system, but terminates and fixes on the lateral guide and the spare part of the rope can be cut and thrown away. Moreover, in this way of implementing the inventive idea only one vertical fixed lateral guide is needed, for the side where the sliding box terminates, which moves.

In particular, Drawing 17 presents the net system with unilateral opening, with one box screwed on the vertical door frame (restraint box) and the pleated net partly unfolded.

Drawing 18 presents the net system with unilateral opening, with one box screwed on the vertical door frame (restraint box) and the pleated net fully folded.

Drawing 19 presents two net systems with unilateral opening, with the pleated net fully folded, placed the one after the other, where the first one has its left box (restraint box) screwed on the vertical door frame, and its right box screwed on the left box of the second system. In case of use of two continuing systems, the ropes of the first system are fixed on the vertical lateral guide, while the ropes of the second system are fixed the same way as in the basic application of the inventive idea, shown in drawings 6 and 7, meaning circle the entire system.

Drawing 20 presents the two net systems of drawing 19, with pleated net partly unfolded. Drawing 21 presents the first step of the placement of the system with unilateral opening at the placement room. That is, the cut of the net, of the boxes and of the lateral guide at their higher ends. At this step the bundle of the set of the short ropes, which is at the higher part of the net, is below the minimum cutting point of the two boxes. The upper cap of the left box (restraint box) is also depicted.

Drawing 22 presents the second step of the placement of the system with unilateral opening at the placement room, where the two lower caps are screwed on the lower ends of the two boxes and one upper cap on the upper end of the restraint box.

Drawing 23 presents the fourth step of placement of the system with unilateral opening at the placement room, where the bundle of short ropes that is at the higher part of the net, comes through the upper cap of the sliding box, via pulley, which is screwed on the upper end of the sliding box and inside the pulley/cap of the vertical fixed lateral guide's upper end, it enters the upper end of the lateral guide.

Drawing 24 presents the final picture of the placed product, with the rope fixed inside the vertical fixed lateral guide.

Drawing 25 presents the way the net is sliding placed between the two boxes (figure 25a), as an autonomous component with the two short ropes bundles (figure 25b), as well as the cross section of the net and the two boxes (figure 25c) demonstrating the way the net enters sliding between them.

An example implementing the present invention follows with a detailed description and reference to the attached drawings.

As depicted in Drawing 1 , the net system with one lateral guide (4) has at its right and left side two sliding boxes (1 and 2), which are in vertical and parallel position to each other. Inside the left sliding box (1) and in its lower part, moves the articulated guide (4) with its one end (3), whereas the other end of the articulated guide (4) is fixed on the detachable basic fixing protrusion (5) located at the lower end of the right sliding box (2). The articulated guide (4) slides inside the lower fixed horizontal guide (6).

Between the two boxes (1 and 2) the pleated net (7) is folded and unfolded into its pleats. ^

The net (7) is crossed over, horizontally, by two sets of restraint short ropes (set la, 3a, 5a and set 2a, 4a, 6a), placed all horizontally and in equal distances from each other. As set is defined the group of short ropes that have as common starting point the same side of the net, either the left or the right one.

The short rope starting from the lowest point of one side of the net crosses horizontally the net and then finishes at the high part of the opposite side. The short rope starting from the highest point of one side of the net crosses horizontally the net and then finishes at the low part of the opposite side (drawing 25, figures 25a and 25b). The side of the net (7) that enters sliding into the box (1) with the articulated guide (4) is the side where the lowest rope starts from (la). The side of the net (7) that enters sliding into the box (2) with the fixing protrusion (5) at the lower end is the side where the highest rope starts from (6a) (drawings 1-5).

The short ropes cross over the net (7) horizontally and alternately; that is, the first short rope (la) belongs to the first set, the right next one (2a) belongs to the second set, the right next (3 a) belongs again to the first set, the right next (4a) belongs again to the second set, etc.

In any case, the lowest and the upper short rope start from opposite sides of the net.

Thus, hereupon, one set (2a, 4a, 6a) has its short ropes all to start from the right side of the net (7) in the right sliding box (2), crossing over, horizontally, the pleated net (7) and in equal distances from each other, directing towards the left box (1) and terminate meeting to the left side of the net (7) in the left sliding box (1) as follows: firstly, the upper (6a) meets the following one (4a) in a common point (9) and hereupon both together (6a and 4a) meet the following short rope (2a) in a common point (10), forming a bundle (11). As a unified bundle (11) they come down all together to the lower part of the sliding box (1). The end of the bundle (11) enters the lower detachable end (18) and supported by a lower pulley (15) comes through and fixes on the last (3) protrusions of the articulated guide (4). Thus, the set of short ropes (2a, 4a, 6a) that started from the right side of the net (7) terminates to the left side of the net (7) in the left sliding box (1).

On the contrary, the other set (la, 3a, 5a) starts and terminates at the same side, circling the entire system. In particular, all the ropes start from the left sliding box (1). They cross over, horizontally, the pleated net (7), in equal distances from each other, directing towards the right box (2) and terminate meeting to the right side of the net (7) inside the right sliding box (2) as follows: firstly, the lower short rope (la) meets the following one (3a) in a common point (12) and afterwards both together (la and 3a) meet the next short rope (5a) in a common point (13) by forming a bundle (14) (figure 25b). As a unified bundle (14) the short ropes cross the right sliding box (2) vertically towards its upper end, where, supported by pulleys (16, 17, 19) they cross over longwise the entire upper horizontal fixed guide (8) from the upper end of the right sliding box (2) to the upper end of the left sliding box (1), where, again supported by pulleys (20, 21) they cross the left sliding box (1) vertically downwards, they enter inside the lower detachable end (18) as a bundle (14) and terminate fixed, via pulley (37), on the end (3) of the articulated guide (4). That is, the short ropes of this set (la, 3a, 5a) terminate as a unified bundle inside the left sliding box (1) also.

Thus, one set of short ropes (2a, 4a, 6a) start from the right side of the net (7) inside the right sliding box (2) and their ends as a bundle (11) terminate at the end (3) of the articulated guide (4) inside the left sliding guide (1), and the other set of short ropes (la, 3a, 5a) start from the left side of the net (7) inside the left sliding box (1) and their ends as a bundle (14) terminate at the end (3) of the articulated guide (4) inside the left sliding box (1) also.

The alternate placement of the sets of ropes provides an ultimate stability and a normal course what regards net's folding and unfolding. In any case, the lowest and the upper short rope start from opposite sides of the net (7).

However, the system works in a similar way, even if the short ropes of the two sets are not placed alternately but in continuity, that is, first all the short ropes of the first set and afterwards all the short ropes of the second set.

Moreover, the two sets may not have an equal number of ropes (Drawings 14 and 15), or only one short rope may start from each side of the net (Drawing 16) but again, the lowest and the upper short rope start from opposite sides of the net (7). Drawings 1 to 5 present the systems' way of movement in progress, during the folding and the unfolding of the pleated net.

When the net (7) is fully folded (Drawing 4), the system is in the starting position. The entire articulated guide (4) is in vertical position inside the left sliding box (1) and its end (3) is located at the upper part of the box. In this position, the system can be either at the centre of the opening (Drawing 4) or at the left part (Drawing 5), or generally at any part of the opening that suits the user.

When the net (7) is partly unfolded (Drawings 2 and 3), the articulated guide (4) is partly in vertical position inside the left sliding box (1) and partly in horizontal position inside the lower fixed horizontal guide (6). The pulleys (20, 19) located at the detachable upper pulleys/caps of the vertical fixed laterals (23, 24) and the pulleys (21, 16, 17) located at the detachable upper ends (35, 36) of the two boxes (1 and 2), allow the free movement of the ropes (11 and 14) and any of the two sliding boxes (1 and 2), or both of them at the same time, either to the left or to the right.

The main feature of the system is that both sets of short ropes terminate and fix as unified bundles (11 and 14) on the end (3) of the articulated guide (4) within the same box (1). That is, the entire system is like a circle that is completed and closes at the end (3) of the articulated guide (4). This makes the working of the entire system easy, because every movement of the boxes (1 and 2) moves the articulated guide (4) as well, inside or outside the left box (1). As a consequence, the bundles of short ropes (11 and 14), bound on the end (3) of the guide (4), move along the guide, the net (7) folds and unfolds, the short ropes that cross it over, stretch and hold it in its place or fold and let it fold in its pleats, and that is the way the system works.

Especially as regards the very wide openings, it is possible to place more than one systems, the one after the other, as depicted in Drawings 6 and 7. In particular, the first system works as analysed above. Hereupon, the second, and every other system that might be applied at the same opening, is completely similar to the working and the accessories of the first system of Drawings 1 to 5. In the example depicted in Drawings 6 and 7, the pleated net (30) of the second system is crossed over two sets of short ropes, horizontally. The first set of short ropes (2b, 4b, 6b) terminates in a unified bundle (26) which is fixed on the last protrusions (31) of the articulated guide (25) at the left sliding box (29), via pulley (46) set in the lower detachable end (18) of the box (29). The second set of short ropes (lb, 3b, 5b) terminates in a unified bundle (27) which also fixes on the last protrusions (31) of the articulation guide (25) at the left sliding box (29), after crossing over, via pulleys (32, 40, 19 and 20), the entire upper horizontal fixed guide (8) and afterwards, via pulley (33) located inside the left sliding box (29), it enters the box (29), as a bundle (27), crosses it over vertically directing downwards and via pulley (38) set in the lower detachable end (18), terminates and fixes on the end (31) of the articulated guide (25).

When two or more systems are used, they can have the right sliding box (2) of the first system, connected to the left sliding box (29) of the second one (Drawing 6) and then the right sliding box (28) of the second one connected with the left sliding box of the next system etc. However, it is not necessary to connect the systems. Thus, they remain autonomous as regards the movement of closing and opening (Drawing 7).

The bundles (11, 4) are fixed by binding on the end (3) of the articulated guide. For their fixing the user has the alternative choice to use the special fixing accessory (34), depicted in Drawing 8. The accessory for the regulation of the ropes' tension (34) which is placed as last or penultimate at the end (3) of the articulated guide (4), upon which the bundle (11) from the set of ropes (2a, 4a and 6a) is fixed, which starts from the right side of the net (7) inside the right sliding box (2) (Drawing 13), and the bundle (14) from the set of ropes of the other set (la, 3a and 5a) which starts from the left side of the net (7) inside the left sliding box (1). The regulator of the ropes' tension (34) has so many holes as the short ropes of the set, for which it will be used and through every hole a short rope passes through.

The counter-terminal accessory (34) has the size and the form of the protrusions of the articulated guide (4, 25), with the lateral projections and the recesses of an ordinary protrusion of the guide. It consists of a main body (44). It also has one (Drawing 8, figure 8b) or more (Drawing 8, figure 8b) bright chambers (43) internally, every chamber has a slit (45) lengthwise its upper part, as well as a security at its back part.

Inside every chamber (43) a screw thread (41) spins, inside a head for the transit of ropes (42) with a projection with wide hole poking out of the slit (45). A short rope passes through every hole, on which it bounds. The head for the transit of ropes (42) is of equivalent form with the internal part of the bright chamber (43), so as to enter sliding into it. Every screw-thread's (41) spin causes a shift of the head (42) back and forth and regulates every rope's volume of tension by the installer.

The system depicted in the Drawings uses two sets with three short ropes each (Drawing 8 figure 8a, Drawings 6-7, Drawing 25 figure 25b), therefor the tension accessories (34) used have three holes each, through which pass the short ropes of the two bundles (11 and 14), which are fixed on the end (3, 31) of the articulated guide (4, 25), one short rope at each hole.

Drawings 9 to 13 depict the way of implementing the present system, which is like a kit and which is adjusted at the placement room in the measurements of the opening about to be covered.

As depicted in Drawing 9, the first step of the mounting procedure at the placement room is conducted as follows: initially, during the placement, the main body of the system consists of the left sliding box (1) and the right sliding box (2), with the pleated net (7) folded between them. The articulated guide (4) is inside the left sliding box (1) in a vertical position. The end of the articulated guide (4) which is outside the left box (1) is fixed on the detachable basic fixing protrusion (5) which is located at the lower end of the right sliding box (2) without being fixed on the box (2) yet. The two upper detachable ends (35, 36) of the left (1) and the right (2) sliding box with their pulleys (21, 16, 17) respectively, are also depicted. The detachable ends (35, 36), at this stage, have not yet been placed at the upper ends of the two sliding boxes, neither the pulleys/covers (20, 19) of the lateral guides (23, 24). The installer takes the measures of the opening to be covered and then cuts and throws away as useless part of the two sliding boxes (1, 2), of the two lateral guides (23, 24) and a part of the pleated net (7). The cutting of the accessories is always done between the minimum and the maximum cutting point. In particular, at least 4-5 mm above the highest short rope (6a), that is, the last horizontal short rope. The point of 4-5 mm above the short rope (6a) is defined as the minimum cutting point of the kit, a sign on the boxes from the manufacturer. The installer can cut the accessories at any height between the two minimum and maximum points, indicated on the boxes and the two vertical fixed lateral guides (23, 24).

The set of ropes (la, 3a, 5a) that ends as a bundle (14) to the upper part of the net (7), is located always below the minimum cutting point of the boxes. At the upper part the net is manufactured with large margin, much larger than the margin at the low part, in order to enable cutting. As depicted in Drawing 10, at the next step of the mounting procedure the upper part of the boxes (1 and 2), of the net (7) and of the lateral guides (23, 24) are cut and thrown away at the part that exceeds the height of the opening, which is about to be covered and consequently the system has obtained its final height, according to the opening, about to be covered. Directly afterwards the lower detachable part (18) is screwed on the lower end of the left sliding box (1) and the detachable basic fixing protrusion (5) on the lower end of the right sliding box (2).

As depicted in Drawing 11 , at the next step of the mounting procedure of the system at the placement room, the upper detachable end (35) is screwed on the upper end of the left sliding box (1) and the upper detachable end (36) on the upper end of the right sliding box (2). At same time, the set of ropes (la, 3a, 5a) that ends as a bundle (14) to the upper part of the net (7), passes through the upper detachable end (36) of the right sliding box (2), via pulley (16).

Hereupon, as depicted in Drawing 12, at the next step of the mounting procedure of the system at the placement room, the bundle (14) passes through the two upper detachable caps/pulleys (19 and 20) of the two lateral guides (24 and 23) and then via pulley (21) enters the upper detachable end (35) which is located at the upper end of the left sliding box (1), in which the articulated guide (4) is enclosed. Then it comes down to the lower detachable end (18) of the box's lower end (1), where via pulley (37) it comes up and is fixed from the side on the end (3) of the articulated guide (4).

As depicted in Drawing 13 at the last step of the mounting procedure of the system at the placement room, the two upper detachable caps with pulleys (20 and 19) through which passes the bundle of ropes (14) that circles the system, are screwed on the two upper ends of the two lateral guides (23 and 24) who are placed on the left and the right lateral vertical door frames. Finally, with the accessory for the regulation of the ropes' tension (34) as last protrusions at the end (3) of the guide (4), the volume of the bundles' tension (14 and 11) is regulated.

Drawings 14, 15 and 16 present the net system with a lower articulated guide with bilateral opening, with the pleated net (7) fully unfolded, in three variations of the primal Drawing 1.

The first variation (Drawing 14) is when the two sets of short ropes have unequal number of ropes, with the set that starts from the left side of the net (7) inside the left sliding box (1) having two short ropes (la, 5 a) and the set that starts from the opposite side having four short ropes (2a, 3 a, 4a, 6a). The lower and the higher rope always start from opposite sides of the net (7).

The second variation (Drawing 15) is again with unequal number of short ropes, starting from the left side of the net (7) inside the left box (1) only one short rope (la) and from the opposite side all the rest (2a, 3a, 4a, 5a, 6a). The lower and the higher rope always start from opposite sides of the net (7).

Finally, the third variation (Drawing 16) is the same system with only one short rope starting from each side of the net, one ( l a) from the left side of the net, the lower possible point inside the left sliding box (1) and one (6a) from the right side of the net, the highest possible point inside the right sliding box (2).

All three variation mentioned above (Drawings 14, 15, 16) are non restrictive examples of implementing the same inventive idea. It is obvious that many more variations as regards the number of ropes can exist, without this indicating that it would be a new invention. However, all short ropes should never start from only one side of the net. One short rope always starts from the lower point (la) of that side of the net which is at the side of the box (1) containing the articulated guide (4) and one short rope (6a) from the higher point of the opposite side of the net, moving in opposite direction to each other. At the intermediary distance between them there can be various number of intermediary short ropes, starting from one or both sides of the net, without restrictions, since the technical function of these intermediary ropes is the resistance of the net to the movement of the wind. The present invention works exactly in the same way and in the case that the user wishes to open the net from one side of the opening (unilateral opening) only, either the left or the right one, and so the box of the side that won't open and close, is screwed and fixed on the door frame and it can now be called "restraint box". At the same time, the set of short ropes which starts from the left side of the net does not have to circle the entire system, but terminates and is fixed on the lateral guide that is screwed on the opposite vertical door frame and the spare part of the rope can be cut and thrown away.

As depicted in Drawings 17 to 24 the invention works with the same accessories and in the same way, as analysed above and depicted in Drawings 1 to 8. The difference in this case is that the box (1) containing the articulated guide is screwed on the vertical left opening and is now called the restraint box. Furthermore, the bundle (14) of the set of ropes (la, 3a, 5a) which starts first from the lowest part of the net (7) passes through the pulleys (16, 17) and spreads longwise the upper horizontal guide (8) until the vertical fixed lateral guide (24), in which it enters via pulley (19) located at the detachable cap and is fixed inside the guide (24) with a fixing accessory (39). Drawings 17 and 18 present that way of implementing the invention with the net (7) partly unfolded (Drawing 17) or fully folded (Drawing 18) and the restraint box (1) screwed on the left vertical opening. Drawings 19 and 20 present the way of implementing the invention on very wide openings, where the placement of more than one systems is possible, the one after the other, relative to the above described procedures and the Drawings 6 and 7. In particular, the first system works as just analysed (Drawings 17 and 18) and the unified the bundle (14) is fixed to the vertical fixed lateral guide (24) with a fixing accessory (39). Hereupon, the second, and every other system, located at the same opening, is exactly similar to the working and the accessories of the first system (Drawings 17 and 18). In the example depicted in Drawings 19 and 20, the pleated net (30) of the second system is crossed over horizontally by two sets of short ropes, where the first set of short ropes (2b, 4b, 6b) terminates in a unified bundle (26) which is fixed on the last protrusions (31) of the articulated guide (25) at the left sliding box (29). The second set of ropes (la, 3b, 5b) terminates as a unified bundle (27) which passes through pulleys (32, 40, 19, 21) spreads longwise the upper horizontal guide (8), then enters the box (1) as a bundle (27), goes vertically downwards and is fixed at the end (3) of the articulated guide (4) of the first system.

In the case of these two systems, the restraint box (1) of the first system is screwed on the vertical lateral door frame. The right sliding box (2) is connected to the left sliding box (29) of the second system and the right sliding box (28) of the second system is connected to the left sliding box of the next system etc.

Furthermore, in the case of the unilateral opening, where the restraint box (1) is screwed on the vertical lateral door frame, the vertical lateral guide (23) is not used for this lateral door frame, but only the vertical lateral guide (24) for the opposite vertical lateral door frame, where the sliding box of the system terminates.

Drawings 21 and 24 present the way to place a system with unilateral opening, that has the form of a kit, at the placement room in the measurements of the opening about to be covered.

As depicted in Drawing 21, the first step of the mounting procedure at the placement room is conducted as follows: initially, during the placement, the system consists of the left restraint box (1) and the right sliding box (2), with the pleated net (7) folded between them. The articulated guide (4) is inside the restraint box (1) in a vertical position. The end of the articulated guide (4) which is outside the left box (1) is fixed on the detachable basic fixing protrusion (5) which is located at the lower end of the right sliding box (2) without being fixed on the box (2) yet. The detachable end (35) of the restraint box (1), which, at this stage, is not placed on the upper end of the box (1) yet is also depicted. The installer cuts and throws away as useless part of the two boxes (1, 2), as well as of the lateral guide (24) and a part of the pleated net (7). The cutting of the accessories is done again between the minimum and the maximum cutting point, always at least 4-5 mm above the highest short rope (6a), that is, the last horizontal short rope. The point of 4-5 mm above the short rope (6a) is defined as the minimum cutting point of the kit, a sign on the boxes from the manufacturer. The installer can cut the accessories at any height between the two minimum and maximum points, indicated on the boxes.

The set of ropes (la, 3a, 5a) that ends as a bundle (14) at the upper part of the net (7), As below the minimum cutting point of the boxes. As depicted in Drawing 22, at the next step of the mounting procedure at the placement room the upper part of the boxes (1 and 2), of the net (7) and of the lateral guide (24) have been cut and thrown away at the part that exceeds the height of the opening about to be covered. Consequently, the system has now obtained its final height. Directly afterwards the lower detachable part (18) is screwed on the lower end of the restraint box (1), the detachable basic fixing protrusion (5) on the lower end of the right sliding box (2) and the upper detachable cap (35) on the upper end of the restraint box (1).

As depicted in Drawings 23 and 24, at the next and final steps of the mounting procedure at the placement room, the bundle (14) comes through the upper detachable end (36) via pulley (16). The upper accessory (36) is screwed on the upper end of the sliding box (2). Then, the bundle (14) continues and passes through the upper detachable cap/ pulley (19) of the vertical fixed lateral guide (24), enters it and is screwed by the side with a fixing accessory (39).

According to the above mentioned, the placement of the kit at the placement room is extremely quick and simple, since it only requires the cutting of the system at the right length, the screw of the detachable caps and the tension of the ropes.

The invention applies to all anti-mosquito nets with a pleated net that move horizontally.