MXPA06010636A - Roller curtain device - Google Patents

Abstract

The invention relates to a curtain device mounted on a shaft (2) about which said curtain (1) can be wound to an open position and unwound into a closed position, a drive wheel (7) fixed coaxially to said shaft (2) and cooperating with said curtain (1) such as to displace the latter between said two positions. The device comprises an oblong flexible control body (11), cooperating with the drive wheel (7), said body (11) being embodied to permit the displacement of the curtain (1) between the open position and the closed position thereof, independently of the slack formed in the curtain (1) and to be able to be displaced along at least one of the lateral edges (4) of the curtain (1) and act upon the region (8) of the latter as opposed to that arranged on the shaft (2).

Description

ROLLER CURTAIN DEVICE DESCRIPTIVE MEMORY The invention relates to a curtain device mounted on an arrow around which this curtain can be wound to an open position and from which it can be unwound to a closed position, a drive wheel which is coaxially secured on this arrow , preferably on both sides of the curtain and cooperating with the latter so as to move it between these two positions. The known devices of this type, especially through documents US 5 655 591, US 5 392 836, US 5,353,859, US 4,690,194, DE 32 45 009, WO 99/19590 A, GB 1 588 438 A, DE 198 20 933 A and EP 1 298 264 A, require the curtain to be stretched while moving between its open position and its closed position. The consequence of this is that the construction of these devices is very complex and very expensive due to the presence of springs, guide pulleys, reduction gears, etc., which generally require a very precise adjustment in order to operate correctly and the which are subject to significant wear and frequent repair, especially in cases where the curtain is immobilized or trapped. One of the essential purposes of the present invention is to counteract these disadvantages by presenting a very simple and efficient device which is economically justified and which allows numerous variants to be developed for various applications. In this way, it is possible to design variants that allow a hermetic seal to be obtained, for example, for refrigerators, containers, silos, utility vehicles such as trucks, ships, wagons, and variants in which the curtain extends horizontally or obliquely. in its closed position, etc. For this purpose, the device according to the invention comprises an oblong control element that is flexible in terms of its length that cooperates with the drive wheel, this element is designed in such a way as to allow, on the one hand, that the curtain is moved between its open position and its closed position independently of the slack in the curtain and, on the other hand, to move it along at least one of the lateral edges of the curtain and to act in the area of the latter opposite to that directed from the side of the arrow mentioned above also independently of the possible slack in the curtain. The control element and its arrangement in the device according to the invention are such that they allow a clearance to be formed in the curtain when it is being moved, without this impeding its operation. This is not possible with the devices according to the prior art in which, on the contrary, all measures are taken to avoid slack. The complex construction of these known devices is the result of this requirement.

Advantageously, the advancing diameter of the driving wheel is, on the one hand, less than the diameter of the rolled portion of the curtain in its open position, and, on the other hand, greater than the diameter of the aforementioned arrow or the rolled portion of the curtain in its closed position. Within the scope of the present invention, the term "advance diameter" means the distance traveled by the control element from the drive wheel during a complete revolution of the latter divided by p. Other details and features of the present invention will become more apparent from the following description of a few types of specific modalities, although not extensive, when taken in conjunction with the accompanying drawings. Figure 1 is a schematic front view of a first embodiment of a curtain device according to the invention; Figure 2 is a schematic perspective view of a part of the curtain device of this first embodiment when the curtain is in the open position; Figure 3 is a view substantially identical to that of Figure 2 when the curtain moves towards its closed position; Figure 4 is a view substantially identical to that of Figure 3 when the curtain moves to the closed position and when the diameter of the rolled portion of the curtain corresponds substantially to the advancing diameter of the driving wheel; Figure 5 is a view substantially identical to that of Figure 4 when the curtain is in its closed position; Figure 6 is a cross section, along the line VI-VI of Figure 1, of a guide rail in which the control element and the side edge of the curtain are guided; Figure 7 is a cross section similar to that of Figure 6, in which the control element has undergone a 90 ° torsion before entering the guide rail; Figure 8 is a side view of a second embodiment of the device according to the invention in the open position; Figure 9 is a side view essentially identical to that of Figure 8 when the curtain moves towards the closed position; Figure 10 is a side view essentially identical to that of Figure 8 when the curtain is in the closed position; Figure 11, drawn on a larger scale, is a detailed representation of the front of the lower part of the curtain showing one of its lateral edges of this second embodiment; Figure 12 is a cross-section along the line XII-XII in Figure 11. Figure 13 is a cross-section along the line XIII-XIII in Figure 9; Fig. 14 is a schematic perspective view of part of a curtain device according to a third embodiment of the invention; Figure 15 is a cross section of a portion of a device according to a fourth embodiment of the invention; Figure 16 is a schematic perspective view of a fifth embodiment; Figure 17 is a schematic front view of a sixth embodiment; Figure 18 is a schematic perspective view of a seventh embodiment with the curtain in an intermediate position; Figure 19 is a schematic longitudinal cross-section along the line XIX-XIX in Figure 18; Figure 20 is a view essentially identical to that of Figure 19 with the curtain in the closed position; and Figure 21 refers to a variant of the seventh embodiment and, represented on a larger scale, is a longitudinal section of part of a guide rail in which a control element is moved. Generally speaking, the present invention relates to a roller curtain device that cooperates with drive means that allow the curtain to move between an open position and a closed position. It should be noted that the curtain can be wound around an arrow which is integral with that of the drive means. The curtain is generally intended to close an opening in a wall or any other opening, cover a pool, an area such as a gazebo, or is used to create a screen, for example in front of a window, etc. Of course, this list is not exhaustive. Within the scope of the present invention, the term, "curtain" refers to any panel or flat surface made of a material that is at least partially collapsible, flexible, semi-rigid, or with one or more reinforcing materials, such as a canvas, a strip of plastic, a hemp cloth or metal sheet, mesh, etc., that can be wrapped around an arrow. However, it should be noted that there is a marked preference for folding flexible curtains formed, for example, by a protective tarpaulin, so that the description given below will be limited to a device in which the curtain is formed by a tarpaulin. A first embodiment of a curtain device is shown in figures 1 to 6. This device includes a curtain 1, which is rolled and unrolled vertically, which is secured with its upper edge to an arrow 2 over an opening 3 and extending substantially over the width of the latter. The curtain 1 can be moved between an open position, as shown in figures 1 and 2, and a closed position, as shown in figure 5. In the open position, the curtain 1 is almost completely wound around the arrow 2 and form a roller 15, while in the closed position, curtain 1 is practically completely unwound from this arrow 2. In certain cases, curtain 1 can be completely wound around arrow 2, in order to maintain an amount maximum free space under the curtain in its open position. When the curtain 1 moves towards its open or closed position, the side edges 4 of the curtain 1, which have an edge roller protruding in relation to the plane of the curtain, are guided on the guide rails 5 mounted on either side of the opening 3 essentially over the entire height of the latter. Both sides of the curtain 1 are equipped with a driving wheel 7, which forms part of the aforementioned driving means, and is coaxially secured on said arrow 2, so that said arrow 2 and this driving wheel 7 are moved to the same angular velocity. Each of these driving wheels 7 cooperates with a control element 11 which allows the curtain 1 to move towards its closed position and which, according to the invention, is freely mounted relative to the curtain 1, especially in relation to the free edge 8 of the latter on which a pushing force must be applied. The drive wheel 7, in particular, consists of a gear wheel, while the control element 11 is formed by a narrow and flexible oblong strip, but not compressible in terms of its length, such as a belt. This strip is provided with a series of holes 10 which are uniformly spaced along its longitudinal direction and which mesh with the teeth 9 on the drive wheels 7 at a constant distance from each other around the periphery of a circle, whose center is located on the axis 6 of the drive wheels 7. In figures 2 to 5, these teeth and holes are not shown for clarity purposes. The diameter d0 of the drive wheels 7, particularly the diameter of advance of these wheels, is lower than the diameter di of the roller 15 when the curtain 1 is in its open position and greater than the diameter d2 of the arrow 2 or the portion of curtain 1 still wound in the closed position. The diameter d2 is usually slightly larger than the diameter of the arrow 2 due to the fact that in the closed position, a small portion of the curtain 1 generally remains coiled in the arrow 2. Preferably, the diameter d is equal to or greater than the diameter. half of the sum of the diameters dj and d2. In the open position, the curtain 1 is practically completely wound around the arrow 2 and forms successive coils 14, as shown in figure 2. In this position, each end of the lower edge 8 of the curtain 1, opposite to that mounted on the arrow 2, is held in the guide rails 5. The control elements 11, whose lower end 16, in the open position is held in the upper part of the guide rails 5 are also guided on the guide rails respective 5 when the curtain 1 is opened and closed as will be described in more detail with respect to Figure 6.

In the open position of the curtain 1, as shown in figure 2, its lower edge 8 is at a distance X below the free end 16 of the corresponding control element 11. This distance allows a certain tolerance in the construction and adjustment of the device according to the invention. The dimensions of the drive wheel and the control element can be calculated according to the displacement of the curtain in order to reduce this distance to zero. When it is desired to move the curtain 1 from its closed position to its open position, the arrow 2 is driven by an electric motor 13. As a result, the roller 15, formed by the coils 14 of the curtain 1 and the driving wheels 7 which they are secured in arrow 2, they are subjected to the same rotation movement. The curtain 1, which is supported by its lateral edges 4 on the guide rails 5, is braked, and in certain cases, even blocked in its movement towards its closed position by friction which inevitably exists between its edges 4 and the rails 5. As a result, when the curtain is closed, the spirals 14 of the roller gradually lengthen and detach from one another forming the play, as shown schematically in FIG. 3. At the same time, the control elements 11 move on the guide rails 5. As mentioned above, insofar as the movement of the curtain 1 is hindered by said friction between the guide rails 5 and the side edges 4 of the curtain 1 , the end 16 of the control elements 11 gradually approaches the lower edge 8 of the curtain 1. When this lower end 16 is at the height of the lower edge 8 of the curtain, this end 16 rests on a pin 17 provided on this lower edge 8, as shown in figure 3. At this time, the control elements 11, actuated by the driving wheels 7, exert a pushing force on the lower edge 8 of the curtain 1 of so that the lateral edges 4 of the curtain 1 move on the guide rails 5 along their longitudinal direction at the same speed as the control element 11. As soon as the diameter of the roller 15, formed by the rolled portion of the curtain 1, becomes smaller than the advancing diameter d0 of the driving wheel 7, the travel speed of the control elements 11 becomes greater than the circumferential travel speed of the roller 15. In this way, the clearance formed disappears as the curtain approaches its closed position, as shown in figure 5. When the curtain 1 is in its closed position, it is almost completely unrolled from the arrow 2. However, as I was already previously, it is possible that the length of the curtain 1 is greater than the height of the opening 3 in order to compensate the adjustment tolerances, for example, that may be present, so that, in this case, a small part of the the curtain can remain coiled in the arrow 2. When the curtain is opened once more, the arrow 2 is driven by the electric motor 13 in the opposite direction to that which closes the curtain 1. In this way, the coils 14 of the curtain 1 which possibly may have remained on the arrow, are initially tensioned around the latter and subsequently the remainder of the curtain 1 is normally wound around the arrow 2. Simultaneously, the control elements 11, which are mounted In a free manner with respect to the curtain 1, they move on the guide rails 5 by means of the action of the drive wheels 7. Since the feed diameter d0 of these drive wheels 7 is initial larger in diameter than the diameter of the rolled portion of the curtain 1, the lower end 16 of the control element 11 gradually separates from the lower edge 8 of the curtain 1. Subsequently, when the diameter of the rolled portion of the curtain 1 becomes larger than the feed diameter of the drive wheels 7, the opposite occurs, and the curtain 1 moves at a higher speed in relation to that of the control elements 11. When the curtain 1 is in its open position, as shown in figures 1 and 2, the distance between the the lower end 16 of the control elements 11 and the lower edge 8 of the curtain 1 is again more or less equal to the distance X or zero. The part of the control element 11 which, in its open position, is located beyond the drive wheels 7 with respect to its lower end 16, can be collected in a housing not shown in the figures.

A cross section of the guide rails 5 is shown schematically in Figure 6. These guide rails 5 have two parallel channels 18 and 19 extending over their entire length. The first channel 18, which has a groove 20 facing the opening 3, houses the side edge 4 of the curtain 1. Its portion adjacent to this side edge 4 extends through the groove 20. In this way, the curtain 1 it can be moved along the longitudinal direction of the guide rails while each of the lateral edges 4 is guided in said first channel 18. The second channel 19 serves as a guide track for the control element 11 as length of the lateral edge 4 of the curtain. In order for the lower end 16 of this control element 11 to be able to press the pin 17 of the lower edge 8 of the curtain 1, a passage 21 is provided between said channels 18 and 19 extending essentially over its entire length. length in order to allow the pin 17 to penetrate the second channel 18 and cooperate in this way with the control element 11. The fact that the pin 17 extends through said passage 21 to the channel 19 results in part of this pin is located below the lower end 16 of the control element 11. The dimensions of said second channel 19 correspond substantially to the dimensions of the control element 11 so that the latter can not be bent or flexed in this channel 19. In this way, the control element 11, which is essentially not compressible in terms of its longitudinal direction, can exert a pushing force on the pin 17 provided on the lower edge 8 of the curtain 1 by means of the drive wheel 7 and thus actuate the curtain 1 towards its closed position. The part of the guide rails 5 defining the channel 19, advantageously extends beyond the level of the axis 6 of the arrow 2, opposite the drive wheel 7 so as to guide the control element as much as possible. This extension is designated with reference 5 'in the figures. The control element 11 consists, for example, of a strip or pole made of p-phenyleneterephthalamide known under the tradename "Keviar", coated with tetrafluoroethylene known under the trade name "Teflon" which measures 2 mm in thickness and 20 mm in thickness. width. This strip has a series of holes 10 which cooperate with the teeth 9 in the drive wheel 7 as already described above. In the embodiment, according to the invention, represented in Figures 1 to 6, the strip which forms the control element 11, extends on the guide rail 5 substantially in the same plane as the curtain 1, as shown in figure 6. The width of the passage 21, which ends in the channel 19, where the control element 11 is housed, is thinner than the latter so that this element can not enter the passage 21.

Since in the embodiment according to Figures 1 to 6, the control element 11 is formed by a narrow flexible strip having a rectangular cross section, it is also possible to provide that the channel 19 of rectangular cross section extends with its side length in a direction perpendicular to the plane of the curtain 1. In this case, the control element undergoes a 90 ° twist in the space between the drive wheel 7 and the guide rail 5. In this way, the width from step 21 may be greater than the thickness of the control element 11, but less than the width of the latter, as shown in figure 7. A second embodiment of the curtain device according to the invention is shown in figures 8 to 13 , which differs from the first embodiment described above in that the control element is formed by a chain 11 which meshes with a conventional cogwheel 7 and which provides a counterweight 22 on the boom from lower 8 of the curtain 1 opposite the edge of the latter which is secured to the arrow 2. The chain 11 is formed by a series of links hinged together around parallel axes, such as a bicycle chain, for example. The feed diameter d0 of the sprocket is less than the diameter di of the roller 15, which is formed when the curtain 1 is in its open position, is greater than the diameter d2 of the still-wound portion 15 of the curtain 1 when the latter It is in the closed position. When the curtain 1 is being closed, through the rotation of the arrow 2, from the open position, as shown in figure 8, the curtain 1 is unwound from this arrow 2 without forming slack due to the action of the weight provided by the counterweight 22. The chain 11 also moves on the guide rail 5 as a result of the action of the sprocket 7. The sprocket 7 is secured coaxially on the arrow 2. This chain 11, which does not form a loop, is dispensed from a container 25 installed below the arrow 2. As mentioned above, when the curtain 1 is moved to its closed position, normally no clearance is formed around the arrow 2 due to the pull action exerted. by the counterweight 22 in the curtain 1. However, when the lateral edges 4 of the curtain 1 are braked on the guide rails 5 due to the action by the wind, which can exert a pushing force in the plane of the curtain 1, while the last closes, curtain movement 1 stops or shuts off. At this time, the play that forms around the arrow 2 and the lower end 16 of the chain 11, which continues to move on the guide rail 5, reaches the lower edge 8 of the curtain 1 and drives it. That is, of course, it is also the case for the first modality described above. Detail of the chain 11 and the pin 17 on the lower edge 8 of the curtain 1 is shown in figure 11. This pin 17 forms part of an L-shaped part 26, whose arm forms the pin 17 and extends parallel with the lower edge 8 of the curtain 1 in the corresponding guide rail 5, the other arm 27 extending parallel to the corresponding lateral edge 4 of the curtain 1. The part 26, in particular, consists of two symmetrical metal plates 28 and 29 which are they mount on either side of the curtain plane 1, so that the latter is held between these two plates 28 and 29. The guide rail 5 characterizes a profile such as to guide the chain 11 along its longitudinal direction without being able to uncouple laterally in relation to this direction. The lateral edge 4 of the curtain is held in the guide rail 5 between the opening 3 and the location where the chain 11 is guided, exactly as in the first embodiment. When a force above a certain value is exerted on the curtain 1 transversely to the plane of the latter, for example, by means of a vehicle running on the curtain 1, the last lateral edges 4 are uncoupled from the guide rails 5. For For this purpose, the lateral edges 4 of the curtain 1 or the guide rails 5 can be designed to deform elastically. Since the chain 11 is not secured to the curtain 1, the pin 17 is easily uncoupled from the chain 11. Figure 14 represents a third embodiment of the curtain device, according to the invention. This essentially differs from the two above described embodiments in that the control element is formed by a loop band 33. This band 33 is guided and driven by the driving wheels 7 mounted on the arrow 2. These driving wheels can , in this case, replaced by pulleys. In the lower part of the opening 3, this band 33 cooperates with a roller 34, which is preferably mounted elastically in relation to the floor by means of spiral springs 40 for example, in order to keep it constantly taut. A contact element 35, formed by a protrusion or hook for example, is mounted on the band 33 between its lower edge 8 and the arrow 2. When the curtain 1 moves under the rotation of the arrow 2, the successive spiers 14 of the roller 15 become larger and form slack as in the first embodiment. Simultaneously, the band 33 moves following the action of the driving wheel 7 and the contact element 35 reaches the lower edge 8. When the contact element 35 touches the pin 17 of the lower edge 8, it exerts a force on this lower edge 8 in order to move curtain 1 towards its closed position. As this contact element 35 moves, the spirals of the curtain 1 unwind and the play decreases. In fact, this contact element 35 fulfills the same role as the free end of the control element 16 of the first and second embodiments. When the curtain is reopened from its closed position, the arrow 2 rotates in the opposite direction of the closure, so that the curtain is wound without play in the arrow 2. Since the diameter of the drive wheel 7 is At the same time, greater than the rolled portion of the curtain 1, the contact element 35 moves away from the lower edge 8 of the curtain until these diameters are substantially equal. Although the remaining portion of the curtain 1 is wound, its lower edge 8 gradually reaches a short distance from the contact element 35, at the moment when the curtain is in the open position. Figure 15 refers to a fourth embodiment which is characterized in relation to the above described embodiments because the curtain 1 is wrapped around a drum 36 which is coaxial with the arrow 2 and which is freely mounted to the latter. The lateral face of this drum 36, directed towards the driving wheel 7, is equipped with a stop 37 which cooperates with a stop 38 located on the driving wheel 7 on the opposite side of the drum 36. Both stops 37 and 38 are mounted at the same distance from the axis 6 of the arrow 2. Initially, when the arrow 2 and the driving wheel 7 begin to rotate in order to move the curtain 1 towards its closed position, the control elements, not shown in the figure 15, move towards the edge of the curtain 1 opposite that mounted on the drum 36 while the latter remains more or less immobile. At the moment when these elements act on this edge, curtain 1 is unrolled at the same linear speed as the control element. The consequence of this is that the drum 36 rotates at an angular velocity less than that of the driving wheel 7 since the diameter of the rolled portion of the curtain is greater than the diameter of the driving wheel 7. As soon as the diameter of the rolled portion of the curtain 1 becomes more or less equal to the diameter of the driving wheel 7, the drum rotates at the same angular velocity as the driving wheel. As the diameter of the rolled portion of the curtain 1 decreases in relation to the diameter of the driving wheel 7, the speed of rotation of the drum 36 increases in relation to that of the driving wheel 7 to the closed position of the curtain. The device can be dimensioned so that the stop 37 comes into contact with the stop 38 when the curtain reaches its closed position. However, it is possible to plan that even in the closed position, these stops 37 and 38 do not touch. In this embodiment, the dimensions of the device are selected so that no clearance is formed in the curtain 1 while closing. During this closing operation, the drum 36 only rotates about its axis 6 by the action of the lower end of the control elements 11 on the pins provided for this purpose at the edge of the curtain 1 opposite one of the side of the arrow 2. There is no contact between stops 37 and 38 while curtain 1 moves to the closed position. When the curtain 1 is opened from its closed position by the rotation of the arrow 2 in the opposite direction in relation to the duration of the closing, the stop 38 of the driving wheel 7 is pressed against the stop 37 of the drum 36 so that the latter is driven by the driving wheel 7 and the curtain 1 is wound around the drum 36. Since when the curtain 1 starts to open, the diameter of the rolled portion of the curtain 1 is less than the diameter of the driving wheel 7, the control element 11 rises faster than the curtain 1.

It is clear that when the opening to be closed by the curtain is very high, the clearance can be formed when the curtain closes when the stops 37 and 38 touch during the closing operation. In this case, this clearance is less important in relation to the other modalities described above. The drum assembly 36 and stops 37 and 38 form a compensator designed to reduce or prevent the formation of slack during the movement of the curtain. The construction of this compensator is very simple and does not require springs, for example. In one embodiment of the curtain device wherein a compensator is provided, it is also possible to secure the lower end of the control element, or the contact element 35, to the pin 17 in a removable manner. In this way, the edge of the curtain 1 opposite one facing the arrow 2 is connected to the control elements through the closing and total opening cycle until the side edges 4 of the curtain 1 are uncoupled from the rails of guidance, for example, by means of a vehicle running in the curtain 1. In this case, the lower end 16 of the control element, or the contact element 35, are automatically separated from the pin 17. In addition, the free end 16 of the shaft serving to cooperate with the curtain preferably be bevelled as the pin 17, in such a way as to facilitate the decoupling of the side edge 5 of the curtain 1 of the guide rails due to an encounter with an obstacle, as indicated above.

In the second embodiment, a beveled end piece can be placed on the free end of the chain 11, in the same manner as the end of the shaft. Figure 16 is relative to a fifth embodiment characterized in relation to the first embodiment shown in Figure 2, in that the end of the strip 11, which forms the control element, is secured at its opposite end to the which acts on the curtain 1 on the arrow 2 and which pulls 11 is wound or unwound between the spirals 14 of the roller 15 of the curtain 1. This avoids having to use a container, as in the second embodiment, to store the part of the control element, formed by a belt or a pole, beyond the impulse wheel. In order to make it possible to compensate the difference in diameter between the rolled portion of the curtain 1 and the driving wheel 7, the strip 11 is provided with sufficient length to allow the outer spiral 12 of the rolled portion of this strip 11 to be able to form a loop in the same manner as the clearance around the arrow 2. Figure 17 refers to a which differs from the above described embodiments in that the control element formed by a non-compressible belt 11, is wound in a spiral manner on a truncated conical pulse wheel 7, toothed or otherwise, the shape of which is such , that during winding and unwinding, the speed of linear movement of the belt corresponds to that of curtain 1 between its open position and its closed position.

When this wheel 7 is not toothed, the grooves, not shown, are preferably provided on the outer surface of the wheel, which spirals about the axis 7 and where the control element 11 moves. A housing 47 is provided. around the driving wheel 7 which characterizes a groove 48 in its lower part, which extends in the plane passing through the axis 6 of the arrow 2 and parallel to the direction of movement of the curtain 1 between its open position and its closed position through which the control element 11 can be wound onto or unrolled from the drive wheel 7. In other cases, for example, to cover the pools, open frames, etc., if on the contrary, to avoid that the lateral edges of the curtain come out of the guide rails, the rails are made of a rigid material or become rigid. In addition, the pins are secured to the edge of the curtain opposite to the side of the arrow where the curtain is mounted and held in a sliding manner on the guide rails. This is possible only for embodiments where the control element is constantly in contact with the pin during the movement of the curtain. Figures 18 to 20 show a mode in which the curtain moves horizontally between an open position and a closed position. The edge 8 of the curtain 1 opposite that of the side of the arrow 2 is formed by a rigid bar, the ends of which form the pins that slide on the guide rails 5 so that the pins can not be uncoupled from the latter. In order to tighten the curtain 1 in its closed position, an aggregate thickness 41, preferably rigid, extends along the entire width of the outer face of the curtain 1, parallel to the axis of the arrow 2 and rests against a rigid transverse bar 42 which also extends parallel to the axis of arrow 2 when the curtain is in the closed position. This crossbar 42 is mounted on the fixed part of the device, such as the guide rails 5. The distance displaced by the curtain from the crossbar 42 to its closed position must thus correspond to the distance between the aggregate thickness 41 and the edge 8 of the curtain 1. In this respect, the position of the transverse bar 42 as well as the aggregate thickness 41 can be adjusted. This allows any clearance that may be present to remain in the portion of curtain 1 upstream from this added thickness 41. This solution is especially important for devices that do not have guide rails for the side edges of curtain 1 or for which it is not possible to provide counterweight of the lower edge of the curtain opposite that of the side of arrow 2. This is the case, for example, when the curtain moves horizontally and whose lateral edges are not guided, as shown in figures 18 to twenty.

Figure 21 refers to a feature that can be adapted in practically all of the embodiments described above, but which is especially useful for relatively long curtains and / or moving with relatively large friction on the guide rails. This may be the case in the embodiment shown in Figures 18 to 20. This feature consists in providing an opening 43 in guide rails 5, near the Impulse wheel for example, between the open position and the closed position of the curtain. , wherein the control element 11 can penetrate during its movement in the guide rail 5 at the moment when an obstruction occurs in the guide rail beyond this opening 43 considering the direction of displacement of the control element 11. In said In this case, the part 11 'of the control element 11 passing through this opening 43 activates a detector 44 which sends a signal to a control station, not shown. This control station can possibly activate a mechanism to correct the problem. In the above embodiments, the control element and the side edges of the curtain move on the same guide rail. However, it is possible to provide a guide rail, or other separate means, for guiding the control element which is completely independent of the guide rails for the side curtain edges and which, for example, allows the control element to be move in a straight path to or from the impulse wheel.

In the curtain devices according to the invention, described above, a pulse wheel 7, which is secured to the arrow 2, is provided on each side of the curtain. In this way, the movement of the corresponding control elements is completely synchronized. Preferably, the curtain 1 is made of a material that allows the successive coils of the rolled curtain to slide together, so that the curtain, for example, is made of a smooth and continuous material, such as protective canvas or possibly material polished plastic for example. When the control element is formed by a non-compressible shank or belt which is not formed in a loop, as the embodiments described above, except for the third embodiment, this control element interacts with the curtain only to move it to its closed position, the opening being made by rotating the arrow 2 about its axis 6 in the opposite direction to that used to close. It is also recommended to select the length of the curtain slightly larger at the height of the opening so that a slight amount of clearance is present around the arrow 2 also in the closed position. This allows compensation of variations in the dimensions of the device and the opening, as well as taking into account the temperature variations that may have an effect on the length of the curtain. Finally, in certain cases, the pin provided on the edge of the curtain opposite that on the side of the arrow can be removed, by means of a lever for example, to allow easy installation and assembly of the device and also to facilitate the reintroduction of this device. pin on the guide rails following a disengagement of the contact from the latter, especially when the edge of the curtain opposite that on the side of the arrow 2 characterizes a rigid bar, as in the seventh embodiment. Although the curtain devices described above are equipped with guide rails, it is clear that the presence of these guide rails is not essential to the invention. Of course, the invention is not limited to the various embodiments described above, and other variants may be considered without departing from the scope of the invention. For small devices, the curtain and drive wheels can be activated manually, for example, by means of a lever mounted on the curtain wrap actuator. In certain cases, if the curtain is made of a sufficiently heavy material, the counterweight can be omitted. In the seventh embodiment, the rigid bar of the edge 8 can be replaced by two headless bolts at each end of this edge that engages the guide rails. Furthermore, in each of the embodiments described above, the means are advantageously provided by allowing a maximum of one spiral of the control element around the driving wheel parallel to the perpendicular plane of the axis of the arrow 2, so that the advancing diameter of the impulse wheel remains more or less constant. In this way, the control element always moves at the same speed during certain closing and opening operations. The aforementioned means are those which prevent the control element from winding itself around the drive wheel.

Claims (16)

NOVELTY OF THE INVENTION CLAIMS

1. - A curtain device mounted on an arrow (2) around which this curtain (1) can be wound to an open position and from which it can be unrolled to a closed position, an impulse wheel (7) coaxially secured in this arrow (2) and cooperating with the curtain (1) in such a way as to move the latter between these two positions, characterized in that it comprises a flexible oblong control element (11) cooperating with the driving wheel (7), this element (11). ) mounted freely in relation to the curtain in such a way as to allow the curtain (1) to move between its open position and its closed position independently of the clearance that can possibly be formed in the curtain (1), on the one hand, and allow that it moves along at least one of the lateral edges (4) of the curtain (1) and act in the area (8) of the last one opposite to that mounted on the arrow (2), on the other hand.

2. The device according to claim 1, further characterized in that the advancing diameter of the driving wheel (7) is smaller than the diameter of the rolled portion of the curtain (1) in its open position, on the one hand, and greater than the diameter of the aforementioned arrow (2) or the rolled portion of the curtain (1) in its closed position, on the other hand.

3. - The device according to claim 1 or 2, further characterized in that the advancing diameter of the driving wheel (7) is greater than or equal to half the sum of the diameter of the rolled portion of the curtain (1) in its open position, and the diameter of the aforementioned arrow (2) or the rolled portion of the curtain (1) in its closed position.

4. The device according to any of claims 1 to 3, further characterized in that means are provided for allowing a maximum of one spiral of the control element (11) to be wound around the driving wheel (7) parallel to a plane perpendicular to the axis (6) of the arrow (2).

5. The device according to any of claims 1 to 4, further characterized in that the control element (11) is essentially not compressible in terms of its length.

6. The device according to any of claims 1 to 5, further characterized in that the aforementioned element (11) is such that it can exert a pushing force on the curtain (1) to bring it to its closed position.

7. The device according to any of claims 1 to 6, further characterized in that the aforementioned control element (11) comprises a non-compressible element in terms of its length.

8. - The device according to any of claims 1 to 7, further characterized in that the drive wheel (7) characterizes a series of protuberances or indentations (9) cooperating with the control element (11) and separated uniformly in relation one with the other along the periphery of a circle, whose center is located on the axis (6) of the aforementioned wheel (7).

9. The device according to claim 8, further characterized in that the control element (11) includes a belt or endless chain.

10. The device according to any of claims 1 to 9, further characterized in that means are provided to prevent the curtain (1) from forming slack when unrolled.

11. The device according to claim 10, further characterized in that these means include counterweight (22) on the edge of the curtain (1) opposite the one mounted on the aforementioned arrow (2).

12. The device according to any of claims 1 to 11, further characterized in that the driving wheel is secured coaxially on the arrow (2) in such a way that it is able to travel at the same angular velocity as this arrow (2). ).

13. The device according to any of claims 1 to 12, further characterized in that it includes guide rails (5) wherein the side edges (4) of the curtain (1) and the control element (11) can be moved parallel to each other.

14. - The device according to any of claims 1 to 13, further characterized in that the drive wheel (7) is such that the control element (11) can spirally wound therearound its axis of rotation.

15. The device according to claim 14, further characterized in that the driving wheel (7) has a truncated conical shape so that, during winding and unwinding of the control element, the linear speed of the latter corresponds essentially to that of the curtain (1) that moves between its open position and its closed position.

16. The device according to any of claims 1 to 15, further characterized in that the compensator is mounted on the aforementioned arrow (2) that allows the rolled portion of the curtain (1) to adapt to the displacement of the control element (eleven ).