HK1118087B - Roller curtain device - Google Patents

Description

Curtain type device

Technical Field

[01] The present invention relates to a device of the curtain type mounted on an axle around which the curtain can be wound in an open position and from which it can be unwound towards a closed position, a drive wheel being preferably fixed coaxially on the axle on either side of the curtain and cooperating with the latter to move the latter between the two positions.

Background

[02] Devices of the kind described are known, in particular those proposed by documents US 5655591, US 5392836, US 5353859, US 4690194, DE 3245009, WO 99/19590 a, GB 1588438A, DE 19820933A and EP 1298264A, which require the curtain to be tensioned during the entire stroke between its open position and its closed position. The consequences of this requirement are: the device is rather complicated and expensive to manufacture, since springs, transmission pulleys, reduction systems, etc., which generally require rather fine adjustment to function well, are prone to severe wear and require frequent maintenance, especially when the curtain is stuck, are necessary.

Disclosure of Invention

[03] One of the objects of the present invention is to overcome said drawbacks and thus to propose a device of simple and effective design which is not only economical but also allows the development of variants for different applications. It is thus possible to design variants which can achieve a tight closure, for example for refrigerators, containers, storage towers, public vehicles such as trucks, ships, carriages, where the curtain extends horizontally or obliquely in its closed position, etc.

[04] To this end, the device according to the invention comprises, in its length direction, a flexible, elongated control member cooperating with the drive wheel, said control member being mounted so as to move the curtain, on the one hand, between its open position and its closed position, despite the possibility of slack forming in the curtain, and, on the other hand, being movable along at least one side edge of the curtain and acting on a section of said curtain opposite to a section mounted on said shaft, also irrespective of the possibility of future slack forming in said curtain.

[05] The control member and its mounting in the device according to the invention are thus such that: when the curtain moves, slack may be formed in the curtain, but this does not prevent its operation.

[06] This is not possible with the devices according to the prior art, in which, on the contrary, various measures are taken to avoid slack. Starting from this requirement, a complex construction of these known devices results.

[07] The pitch diameter of the drive wheel is advantageously smaller on the one hand than the diameter of the part of the curtain wound in its open position and, on the other hand, larger than the diameter of said shaft or than the diameter of the part of the curtain wound in its closed position.

[08] Within the scope of the present invention, it must be understood that the term "pitch circle diameter (dam tournipridif)" refers to: the distance which the control member has traveled during one revolution of the drive wheel from the drive wheel is divided by a number pi.

Drawings

[09] Further details and features of the invention will emerge from the following description of a few specific embodiments, given by way of non-limiting example with reference to the accompanying drawings.

[10] Fig. 1 is a schematic front view of a first embodiment of a curtain device according to the invention.

[11] FIG. 2 is a schematic perspective view showing a part of the curtain device of the first embodiment when the curtain is in its open position.

[12] FIG. 3 is a view similar to FIG. 2 when the curtain is moved towards its closed position.

[13] FIG. 4 is a view similar to FIG. 3 when the curtain is moved towards its closed position and when the diameter of the wound portion of the curtain substantially corresponds to the diameter of the pitch circle (dam [ tre ] primatif) of the driving wheel.

[14] FIG. 5 is a view similar to FIG. 4 when the curtain is in its closed position.

[15] FIG. 6 is a cross section of the slide, taken along the line VI-VI of FIG. 1, in which the control organ and the lateral edges of the curtain are guided.

[16] FIG. 7 is a cross-sectional view similar to FIG. 6, in which the control member is subjected to a 90 twist before entering the slide.

[17] FIG. 8 is a side view of a second embodiment of the device according to the invention in the open position.

[18] FIG. 9 is a side view similar to FIG. 8 when the curtain is moved towards its closed position.

[19] FIG. 10 is a side view similar to FIG. 8 when the curtain is in the closed position.

[20] FIG. 11 is a detailed front view of the lower part of the curtain of said second embodiment at one of its side edges.

[21] FIG. 12 is a cross-section taken along line XII-XII in FIG. 11.

[22] FIG. 13 is a cross-section taken along line XIII-XIII in FIG. 9.

[23] Fig. 14 is a schematic perspective view of a part of a curtain device according to a third embodiment of the invention.

[24] FIG. 15 is a cross-sectional view of a portion of a device according to a fourth embodiment of the invention.

[25] FIG. 16 is a schematic perspective view of a fifth embodiment.

[26] FIG. 17 is a schematic perspective view of a sixth embodiment.

[27] FIG. 18 is a schematic perspective view of the seventh embodiment with the curtain in an intermediate position.

[28] FIG. 19 is a longitudinal schematic section taken along line XIX-XIX in FIG. 18.

[29] FIG. 20 is a view similar to FIG. 19 with the curtain in the closed position.

[30] Fig. 21 is a variant relating to the seventh embodiment and it shows, on an enlarged scale, a longitudinal section of a portion of the slide in which a control organ moves.

Detailed Description

[31] Generally, the present invention relates to windable curtain devices that cooperate with drive means to move the curtain between an open position and a closed position. It is important to note that the curtain may be wound about a common axis with the drive means. Curtains are generally used to close a door opening or any other opening in a wall, to cover a swimming pool, a space such as a corridor, to form a shelter, for example in front of a window, etc. Of course, this enumeration is limited.

[32] Within the scope of the present invention, the term "curtain" includes any panel or flat surface that can be wound around an axis, said panel or flat surface being made of an at least partially soft, flexible, semi-rigid material or provided with one or more reinforcements such as tarpaulins, plastic strips, metal meshes or sheets, frames or the like.

[33] It is however necessary to point out that a flexible curtain, for example formed by an awning cloth, is obviously preferred, so that the following description will be limited to a device in which the curtain is formed by an awning cloth.

[34] A first embodiment of a curtain device is shown in fig. 1 to 6. The device comprises a vertically wound and unwound curtain 1, which is fixed at its upper edge to an axle 2 disposed above a door opening 3 and extending substantially over the entire width of the opening. The curtain 1 is movable between an open position as shown in fig. 1 and 2 and a closed position as shown in fig. 5. In the open position, the curtain 1 is almost completely wound around the shaft 2 and forms a spool 15, while in the closed position, the curtain 1 is almost completely unwound from said shaft 2. In some cases, the curtain 1 may be completely wound around the shaft 2 so as to maintain maximum free space under the curtain in its open position.

[35] When the screen 1 is moved towards its open position or towards its closed position, the side edges 4 of the screen 1, which have flanges projecting with respect to the plane of the screen, are guided in sliding tracks 5, said sliding tracks 5 being mounted on either side of the door opening 3, substantially over the entire height of the latter.

[36] Each side edge of the curtain 1 is provided with a driving wheel 7, which is an integral part of said driving means, which is coaxially fixed to said shaft 2, so that said shaft 2 and said driving wheel 7 move at the same angular velocity. Each driving wheel 7 cooperates with a control organ 11 for moving the curtain 1 towards its closed position, which control organ, according to the invention, is mounted freely with respect to the curtain 1, in particular with respect to the free edge 8 of the curtain 1, on which free edge 8 of the curtain 1 a thrust can be exerted.

[37] In particular, the drive wheel 7 is formed by a toothed wheel, while the control member 11 is formed by a flexible, narrow and long strip, but incompressible in its length direction, like a belt. The strip is provided with a continuous row of holes 10 which are at the same constant distance from each other in its longitudinal direction and which engage with teeth 9 provided on the drive wheel 7, the teeth on the drive wheel 7 being at a constant distance from each other along the periphery of a circle whose centre is located on the axis 6 of the drive wheel 7. In fig. 2 to 5, the teeth and holes are not shown for clarity.

[38]Diameter d of the drive wheel 7₀In particular the pitch diameter of these driving wheels, is smaller than the diameter d of the roller 15 when the curtain 1 is in its open position₁And is larger than the diameter d of the shaft 2₂Or larger than the diameter of the still-wound portion of the curtain 1 in the closed position. In fact, the diameter d₂Typically slightly larger than the diameter of the shaft 2, since a small portion of the curtain 1 generally remains wound on the shaft 2 when in the closed position.

[39]Diameter d₀Preferably equal to or greater than the diameter d₁And d₂Half of the sum.

[40] In the open position, the curtain 1 is almost completely wound on the shaft 2, forming a continuous spiral 14, as shown in figure 2. In this position, each end of the lower edge 8 of the curtain 1 is maintained in the slide 5, said lower edge 8 being opposite the edge mounted on the shaft 2.

[41] The lower end 16 of the control organ 11, in the open position, remains on the upper part of the slide 5, the control organ 11 also being guided in the corresponding slide 5 when the curtain 1 is opened and closed, as will be described in detail in connection with fig. 6.

[42] In the open position of the curtain 1, as shown in figure 2, its lower edge 8 is at a distance X from the one below the free end 16 of the control organ 11. Said distance allows for certain manufacturing tolerances and for adjusting the device according to the invention. It is possible to calculate the dimensions of the driving wheel and of the control organ on the basis of the displacement of the curtain in order to reduce said distance to zero.

[43] When the curtain 1 is to be moved from its open position to its closed position, the shaft 2 is driven by the motor 13. The winding drum 15 formed by the spirally wound layer 14 of the curtain 1 and the driving wheel 7 fixed to the shaft 2 are thus subjected to the same rotational movement. The curtain 1 is maintained in the sliding rail 5 by its side edges 4, and due to the friction that must exist between these side edges 4 and the sliding rail 5, the curtain 1 slows down in moving towards its closed position, in some cases even the curtain 1 gets stuck. The consequence of this is that when the curtain is closed and activated, the spirally wound layer 14 of the roll gradually expands and detaches layer by layer, with a consequent formation of slack, as schematically represented in figure 3. At the same time, the control organ 11 moves in the slide 5.

[44] As described above, since the movement of the curtain 1 is hindered by the presence of the friction between the slide 5 and the side edge 4 of the curtain 1, the end 16 of the control organ 11 comes closer to the lower edge 8 of the curtain 1. At the moment when the lower end 16 is at the level of the lower edge 8 of the curtain, the end 16 of the control organ 11 abuts against a stop pin 17 arranged at the lower edge 8, as shown in figure 3.

[45] From this moment on, the control organ 11, driven by the driving wheel 7, exerts a thrust on the lower edge 8 of the curtain 1, causing the side edge 4 of the curtain 1 to move in the slide 5 along its longitudinal direction at the same speed as the control organ 11.

[46]Once the diameter of the roll 15 formed by the winding portion of the curtain 1 becomes smaller than the pitch diameter d of the driving wheel 7₀At this time, the moving speed of the control device 11 becomes larger than the circumferential moving speed of the drum 15. Thus, the slack formed disappears as the curtain approaches its closed position, as shown in FIG. 5.

[47] At the moment the curtain 1 is in its closed position, the curtain 1 is almost completely unwound from the shaft 2. However, as mentioned above, it is possible for the length of the curtain 1 to be greater than the height of the door opening 3, for example in order to be able to compensate for possible adjustment tolerances, with the result that in this case a small part of the curtain may still remain wound on the shaft 2.

[48] When the curtain is re-opened, the shaft 2 is driven by the motor 13 in a direction opposite to the closing direction of the curtain 1. Thus, it is possible to still stay the spirally wound layer 14 of the curtain 1 wound on the shaft 2, being tightened around the shaft 2 for the first time, and then, the remaining portion of the curtain 1 is normally wound around the shaft 2.

[49]At the same time, the control organ 11, mounted freely with respect to the curtain 1, moves in the slide 5 under the action of the driving wheel 7. Since initially the pitch diameter d of the drive wheels 7₀Larger than the diameter of the winding portion of the curtain 1, the lower end 16 of the control organ 11 is progressively distanced from the lower edge 8 of the curtain 1. Then, when the diameter of the winding portion of the curtain 1 becomes larger than the pitch circle diameter of the driving wheel 7, the opposite effect is produced, and the curtain 1 undergoes movement at a speed larger than that of the control work 11.

[50] When the curtain 1 is in its open position, as shown in figures 1 and 2, the distance between the lower end 16 of the control organ 11 and the lower edge 8 of the curtain 1 is again substantially equal to the distance X or to zero.

[51] In the open position, the part of the control member 11 outside the drive wheel 7 with respect to the lower end 16 of the control member 11 can be collected in a box, not shown.

[52] The sectional illustration of the slide rail 5 is illustrated in fig. 6. The slide rail 5 comprises two parallel channels 18 and 19, which extend over the entire length of the slide rail.

[53] The side edge 4 of the curtain 1 is mounted in a first channel 18 having a slot 20 directed towards the door opening 3. The curtain portion adjacent to said side edge 4 extends through the slot 20. Thus, the curtain 1 can move in the longitudinal direction of the slide during the guiding of each side edge 4 in said first channel 18.

[54] The second channel 19 serves as a guide channel for guiding the control organ 11 along the side edge 4 of the curtain.

[55] In order to allow the lower end 16 of the control member 11 to abut against the stop 17 of the lower edge 8 of the curtain 1, a channel 21 is provided between said channels 18 and 19, which extends substantially over the entire length of said channels, so as to allow the stop 17 to enter the second channel 19 and thus to cooperate with the control member 11.

[56] The stop 17 extends through the passage 21 up to the channel 19, which causes: a part of said stop pin is located below the lower end 16 of the control organ 11.

[57] The dimensions of said second channel 19 substantially correspond to the dimensions of the control organ 11, so that the control organ 11 does not bend in the second channel 19. For this purpose, the control member 11, which is substantially incompressible in its longitudinal direction, can exert a thrust force via the drive wheel 7 on the stop 17 provided at the lower edge 8 of the curtain 1 and thus bring the curtain 1 towards its closed position.

[58] The portion of the slide 5 that delimits the channel 19 advantageously extends beyond the level of the axis 6 of the shaft 2 and against the drive wheel 7, so as to be maximally guided by the control member 11. This extension is marked with 5' in the figure.

[59] For example, the control member 11 is a strip of p-phenylene terephthalate (p-phenylene terephthalamide), known commercially as "Kevlar", coated with a coating of tetrafluoroethylene known commercially as "Teflon", having a thickness of 2 mm and a width of 20 mm. The strip is provided with a continuous hole 10 which cooperates with the teeth 9 on the drive wheel 7, as already described above.

[60] According to the invention, in the embodiment of the device shown in figures 1 to 6, the strip forming the control organ 11 extends substantially in the same plane as the curtain 1, in the slide 5, as can be seen from figure 6. The width of the channel 21 reaching the channel 19 housing the control organ 11 is smaller than the width of the control organ 11, so that the control organ 11 cannot enter the channel 21.

[61] Since in the embodiment according to fig. 1 to 6 the control member 11 is formed by a narrow, flexible strip and is rectangular in cross-section, it is also possible to design: the channel 19 of rectangular section extends with its large side edges in a perpendicular direction with respect to the plane of the curtain 1. In this case, the control member is twisted by 90 ° in the space between the drive wheel 7 and the slide 5. Therefore, the width of the passage 21 is larger than the thickness of the control gear 11 but smaller than the width of the control gear 11, as shown in fig. 7.

[62] In figures 8 to 13 a second embodiment of the curtain device according to the invention is shown, which differs from the first embodiment mainly in that its control means are formed by a chain 11, said chain 11 being in mesh with a conventional toothed wheel 7, and in that a ballast 22 is provided on the lower edge 8 of the curtain 1 opposite to the edge of the curtain fixed to the shaft 2. The chain 11 is formed by successive links hinged to each other around parallel axes, as is the case with chains for bicycles.

[63]Pitch diameter d of gear₀Smaller than the diameter d of the drum 15 formed when the curtain 1 is in its open position₁But is larger than the diameter d of the still-wound portion 15 of the curtain 1 when the curtain 1 is in the closed position₂。

[64] When the curtain 1 is closed by the rotation of the shaft 2 from the open position, as shown in fig. 8, the curtain 1 is unfolded from the shaft 2 without any slackening due to the weight of the ballast 22.

[65] The chain 11 also moves in the slide 5 due to the action of the gear 7. The gear wheel 7 is coaxially fixed on the shaft 2. The chain 11, which is not closed on its own, emerges from a box 25 placed below the shaft 2.

[66] As mentioned above, when the curtain 1 is moved towards its closed position, there is generally no slack formed around the shaft 2 under the pulling action exerted by the ballast 22 on the curtain 1.

[67] However, when the side edges 4 of the curtain 1 are blocked from moving in the slide rails 5 under the action of the wind which may exert a thrust on the plane of the curtain 1 during the closing of the curtain 1, the movement of the curtain 1 stops or slows down. At this time, slack is formed around the shaft 2, and the lower end portion 16 of the chain 11, which continues to move in the slide rail 5, approaches the lower edge 8 of the curtain 1 and drives the lower edge 8 of the curtain 1. This is of course also the case for the first embodiment described above.

[68] The chain 11 and the stop pin 17 on the lower edge 8 of the curtain 1 are shown in detail in figure 11. The stop 17 is part of an L-shaped element 26, one arm of which constitutes the stop 17 and extends in the respective slide 5 parallel to the lower edge 8 of the curtain 1, and the other arm 27 extends parallel to the respective side edge 4 of the curtain 1. The element 26 is in particular made up of two symmetrical metal plates 28, 29 fixed on either side of the plane of the curtain 1, so that the curtain 1 is clamped between the two plates 28 and 29.

[69] The slide 5 has a profile so as to guide the chain 11 in its longitudinal direction without the chain 11 being removed laterally with respect to the slide. The side edges 4 of the curtain are maintained in the slide 5 between the door opening 3 and where the chain 11 is guided, exactly as in the first embodiment.

[70] When a force greater than a certain value is applied laterally on the curtain 1 in the plane of the curtain 1, for example by the action of a vehicle hitting the curtain 1, the side edges 4 of the curtain 1 come out of the slide 5. For this reason, it is expected that the side edge 4 of the curtain 1 or the slide rail 5 may be elastically deformed. Since the chain 11 is not fixed to the curtain 1, the stopper pin 17 is easily released from the chain 11.

[71] In fig. 14, a third embodiment of the curtain device according to the invention is shown, which differs from the first two embodiments mainly in that the control organ is formed by a belt 33, which belt 33 is closed around itself. The belt 33 is guided and driven by a drive wheel 7 fixed to the shaft 2. In this case, the drive wheel is formed by a pulley.

[72] In the lower part of the door aperture 3, said belt 33 cooperates with a small pulley 34, preferably mounted in an elastic manner with respect to the ground, for example by means of a helical spring 40, so as to permanently maintain it in tension.

[73] A contact element 35, for example formed by a projection or a hook, is fixed to the belt 33 between the lower edge 8 and the shaft 2.

[74] When the curtain 1 is unwound due to the rotation of the shaft 2, the continuous spirally wound layer 14 of the winding drum 15 expands and forms a slack as in the first embodiment. At the same time the belt 33 is moved by the action of the drive wheel 7 and the contact element 35 approaches the lower edge 8. When the contact element 35 comes into contact with the stop 17 of the lower edge 8, it exerts a force on said lower edge 8 to move the curtain 1 towards its closed position. With the movement of the contact element 35, the spirally wound layer of the curtain 1 is unwound and the slack is reduced. In fact, said contact element 35 functions in the same way as the free end 16 of the control organ of the first and second embodiments.

[75] When the curtain 1 is opened from its closed position, the shaft 2 is rotated in a direction opposite to the closing direction, so that the curtain is wound on the shaft 2 without slack. Since the diameter of the driving wheel 7 is greater at this moment than the diameter of the winding portion of the curtain 1, the contact element 35 is distanced from the lower edge 8 of the curtain until said diameters are substantially equal. During winding of the rest of the curtain 1, its lower edge 8 gradually approaches until a small distance from the contact element 35, at which time the curtain is in its open position.

[76] Figure 15 relates to a fourth embodiment, which is compared with the previous one, characterised in that the curtain 1 is wound around a roller 36, said roller 36 being coaxial with the axis 2 and being freely mounted on said axis. The side plane of said drum 36 directed towards the drive wheel 7 is equipped with a stop 37, said stop 37 cooperating with a stop 38, said stop 38 being on the opposite side of the drive wheel 7 to the drum 36. The two stops 37 and 38 are mounted at the same distance from the axis 6 of the shaft 2.

[77] First, when the shaft 2 and the driving wheel 7 rotate to move the curtain 1 towards its closed position, the control organ (not shown in fig. 15) moves towards the edge of the curtain 1 opposite to the edge of the curtain 1 mounted on the roller 36, while the roller 36 remains substantially stationary. At the moment when said organ acts on said edge, the curtain 1 is unwound at the same linear speed as the control organ. As a result, since the diameter of the curtain winding portion is larger than the diameter of the driving wheel 7, the drum 36 rotates at a lower angular velocity than the driving wheel 7.

[78] Once the diameter of the winding portion of the curtain 1 becomes substantially equal to the diameter of the driving wheel 7, the drum rotates at the same angular speed as the driving wheel 7. As the diameter of the wound portion of the curtain 1 decreases relative to the diameter of the driving wheel 7, the rotational speed of the drum 36 increases relative to the rotational speed of the driving wheel 7 up to the closed position of the curtain. The device may be dimensioned such that the stop 37 will come into contact with the stop 38 at the moment the curtain reaches its closed position. However, it is possible to see that: even in the closed position, the stops 37 and 38 do not touch.

[79] In this embodiment, the dimensions of the device are chosen so that when the curtain 1 is closed, no slack is formed in the curtain 1. During closing, at the lower end of the control organ 11, the roller 36 is simply rotated about its axis 6 by acting on a stop pin arranged for this purpose at the edge of the curtain 1, which is opposite to the edge of the shaft 2 on the side. When the above-described movement toward the closed position of the curtain 1 is performed, there is no contact between the stoppers 37 and 38.

[80] When the curtain 1 is opened from its closed position by rotation of the shaft 2 in the opposite direction to that during closing, the dogs 38 of the drive wheel 7 abut against the dogs 37 of the roller 36, so that the drive wheel 7 actuates the dogs 37 of the roller 36 and the curtain 1 is wound around the roller 36. Since the diameter of the winding portion of the curtain 1 is smaller than the diameter of the driving wheel 7 when the opening of the curtain 1 is started, the control organ 11 ascends faster than the curtain 1.

[81] It is clear that when the door opening closed by the curtain has a great height, slack is formed in the closing of the curtain 1 when the stops 37 and 38 come into contact during said closing. In this case, however, the severity of the slack is reduced relative to the other embodiments described above.

[82] To reduce or avoid slack formation during curtain movement, the roller 36 and stops 37, 38 are integrally formed as a compensator. The compensator is simple to manufacture and does not require, for example, a spring.

[83] In an embodiment of the curtain device with compensator, it is also possible to fix the lower end of the control member or the contact element 35 to the stop pin 17 in a detachable manner. The edge of the curtain 1 opposite to the edge facing the axis 2 is therefore connected to the control organ during the whole closing or opening cycle, and this occurs until the side edge 4 of the curtain 1 comes out of the slide, for example under the action of the vehicle which hits the curtain 1. In this case, the lower end 16 of the control organ or the contact element 35 automatically disengages from the stop pin 17.

[84] In addition, the free end 16 of the strip, which should cooperate with the curtain, is preferably inclined, like the stop 17, so as to allow the side edge 5 of the curtain 1 to be easily removed from the slide by the obstacle, as described above.

[85] In the second embodiment, an inclined toe is provided at the free end of the chain 11 in the same way as the end of the strip.

[86] Fig. 16 relates to a fifth embodiment, which is characterized in comparison with the first embodiment, in particular represented on fig. 2, in that the end of the strip 11 forming the control organ is fixed by its end opposite the end that should act on the curtain 1 on the shaft 2, and in that said strip 11 is wound or unwound between the spiral winding 14 of the winding drum 15 of the curtain 1. This avoids the use of a case as in the second embodiment to house the control member portion formed by a narrow strip outside the drive wheel.

[87] In order to be able to compensate for the difference in diameter between the wound portion of the curtain 1 and the driving wheel 7, it is possible to consider: the strip 11 has a sufficient length so that the outer spiral-wound layer 12 of the wound portion of said strip 11 forms a closed loop in the same way as the relaxation around the shaft 2.

[88] Figure 17 relates to an embodiment which differs from the previous one in that the control means formed by the incompressible strip 11 is wound in a helical manner on a truncated-cone shaped driving wheel 7, toothed or not, said strip being shaped so that, both when wound and when unwound, the linear movement speed of the strip corresponds to the linear movement speed of the curtain 1 between its open position and its closed position.

[89] When the wheel 7 is not a gear, it is preferable to provide grooves (not shown) in the outer surface of the wheel 7, which extend helically around the axis 6 and in which the control organ 11 moves. Around the driving wheel 7 there is provided a box 47 having, in its lower part, a slot 48, said slot 48 extending in a plane passing through the axis 6 of the shaft 2, said plane being parallel to the direction of movement of the curtain 1 between its open position and its closed position, through which slot 48 the control member 11 can be wound on the driving wheel 7 or unwound from the driving wheel 7.

[90] In other cases, such as for example swimming pools, balconies, etc., the slide is made of a rigid material or is hardened if it is instead necessary to avoid the side edges of the curtain coming out of the slide. Further, a stopper pin is fixed to the edge of the curtain and the edge of the side of the shaft on which the curtain is mounted, and the stopper pin is maintained to slide in the slide rail. This is therefore only possible with such an embodiment, in which the control element is permanently in contact with the stop pin during the movement of the curtain.

[91] Fig. 18 to 20 indicate an embodiment in which the curtain is horizontally moved between an open position and a closed position. The edge 8 of the curtain 1 opposite the side edge of the shaft 2 is formed by a rigid rod whose end forms a protruding pin which is slidingly engaged in the sliding track 5 so that it cannot come out of the latter.

[92] In order to make the curtain 1 taut in its closed position, an ultra-thick portion 41, which is preferably rigid, extends parallel to the axis of the shaft 2 over the full width of the outer surface of the curtain 1, and rests, in the closed position of the curtain 1, on a rigid cross-bar 42, which cross-bar 42 also extends parallel to the axis of the shaft 2. The rod 42, just like the sliding rail 5, is mounted on a fixed part of the device.

[93] Therefore, it is necessary to make the distance which the curtain passes from the rod 42 up to the closed position of the curtain correspond to the distance between the super-thick portion 41 and the edge 8 of the curtain 1. For this reason, the position of the rod 42 is adjustable as is the position of the super-thick portion 41.

[94] This allows the possible occurrence of slack to remain in the upstream curtain 1 portion of the super-thick portion 41. This solution is particularly important for devices that do not include slide rails at the side edges of the curtain 1 or for devices that are not possible to equip the lower edge of the curtain opposite to one side edge of the shaft 2 with weights. This is the case, for example, when the curtain whose side edges are not guided is moved horizontally as shown in fig. 18 to 20.

[95] Fig. 21 relates to a feature which is practically applicable to all of the above embodiments, but which is particularly useful for relatively long curtains and/or curtains which move with high friction in a slide. This may be the case in the embodiments indicated in fig. 18 to 20.

[96] Said feature is that, for example, between an open position and a closed position, an opening 43 is provided in the slide 5 in the vicinity of the drive wheel, and when the control member 11 is moved in the slide 5, the control member 11 can enter the opening 43 at the instant when a jam occurs in the slide downstream of said opening 43, taking into account the direction of movement of the control member 11.

[97] In this case, the portion 11' of the control member 11 passes through said opening 43 and acts on a detector 44, said detector 44 then sending a signal to a control station (not shown). The control station may activate a mechanism to remedy the generated problem.

[98] In the above embodiment, the control organ and the side edges of the curtain move in the same slide. However, a slide rail or other separating device can be provided for guiding the control member, which slide rail is completely independent of the slide rail for the curtain side edge and can, for example, move the control member from or towards the drive wheel over a linear stroke.

[99] In the above-described curtain device according to the invention, a drive wheel 7 fixed to the shaft 2 is provided at each side edge of the curtain. The movements of the respective control organs are thus completely synchronized.

[100] The screen 1 is preferably made of a material which allows the successive spiral layers of the screen to slide over each other, so that for example the screen is made of a smooth and continuous material, for example a possibly smooth plastic tarpaulin.

[101] When the control member is formed by an incompressible strip which does not close on itself, as in the above-mentioned embodiments other than the third, said control member acts only on the curtain to move it towards its closed position, opening being achieved by rotation of the shaft 2 about its axis 6 in a direction opposite to that during closing.

[102] It is also advisable to choose the length of the curtain to be slightly greater than the door opening, so that there is also a slight slack around the shaft 2 in the closed position. This compensates for variations in the dimensions of the device and the door aperture and may take into account variations in temperature that may have an effect on the curtain length.

[103] Finally, in some cases the stop provided at the edge of the curtain opposite the side edge of the shaft may be removable, for example by means of a lever, so that the installation and assembly of the device can be carried out more easily and the re-insertion of said stop in the slide is also easier after the curtain has been extracted from said slide, in particular when the edge of the curtain opposite the side edge of the shaft 2 has a rigid rod, as described in the seventh embodiment.

[104] Although the above-described curtain devices are all equipped with sliding rails, it is clear that the presence of said sliding rails is not essential to the invention.

[105] Of course, the invention is not limited to the different embodiments described above, but other variants are also conceivable without departing from the scope of the invention.

[106] To reduce the size of the device, the curtain and the driving wheel can be operated manually, for example by means of a lever mounted on the curtain winding shaft.

[107] In some cases, if the curtain is made of a sufficiently heavy material, the ballast may be eliminated.

[108] In a seventh embodiment, the stiff bar of the edge 8 can be replaced by two end posts (p1ot) at each end of the edge entering the slide rail.

[109] Furthermore, in each of the above embodiments, means are advantageously provided which enable a helically wound layer of the control member to be wound around the drive wheel to the maximum extent in a plane parallel to a plane perpendicular to the axis of the shaft 2, so that the pitch diameter of the drive wheel remains substantially constant. Thus, the control member always moves at the same speed when the curtain is closed and opened. The above-mentioned means prevent the control member from winding around itself around the drive wheel.

Claims (16)

1. Curtain-type device mounted on an axle (2), said curtain (1) being windable about said axle (2) towards an open position and being unwound towards a closed position, a drive wheel (7) being coaxially fixed to said axle (2) and cooperating with said curtain (1) to move said curtain (1) between said two positions,

characterized in that it comprises a flexible elongated control organ (11) cooperating with said driving wheel (7), said control organ (11) being mounted freely with respect to said curtain so as to allow, on the one hand, the movement of said curtain (1) between its open position and its closed position without being affected by any slack that may form in the future in said curtain (1), and, on the other hand, the control mechanism being movable along at least one side edge (4) of said curtain (1) and acting on a section (8) of said curtain (1) opposite to the section mounted on said shaft (2).

2. A device according to claim 1, characterised in that the pitch diameter of the driving wheel (7) is, on the one hand, smaller than the diameter of the part of the curtain (1) wound in its open position and, on the other hand, the pitch diameter of the driving wheel (7) is larger than the diameter of the shaft (2) or of the part of the curtain (1) wound in its closed position.

3. A device according to claim 1 or 2, characterised in that the pitch diameter of the driving wheel (7) is equal to or greater than half the sum of the diameter of the part of the curtain (1) wound in its open position and the diameter of the shaft (2), or the pitch diameter of the driving wheel (7) is equal to or greater than half the sum of the diameter of the part of the curtain (1) wound in its open position and the diameter of the part of the curtain (1) wound in its closed position.

4. Device according to claim 1 or 2, characterized in that means are provided for: said part maximizing the winding of a spiral winding of the control member (11) around the drive wheel (7) in a plane parallel to a plane perpendicular to the axis (6) of the shaft (2).

5. A device according to claim 1 or 2, characterized in that the control organ (11) is incompressible in its length direction.

6. Device according to claim 1 or 2, characterized in that said control organ (11) is such as to exert a thrust on said curtain (1) to bring it to its closed position.

7. A device according to claim 1 or 2, characterized in that the control organ (11) comprises an incompressible element in its length direction.

8. Device according to claim 1 or 2, characterized in that the driving wheel (7) has a series of projections or recesses (9) which cooperate with the control organ (11) and which extend at a constant distance from each other according to the circumference of a circle, the centre of which is located on the axis (6) of the driving wheel (7).

9. Device according to claim 8, characterized in that said control member (11) comprises an endless belt or an endless chain.

10. Device according to claim 1 or 2, characterized in that means are provided in the curtain (1) which make it possible to avoid the formation of slack in the curtain (1) when the curtain (1) is deployed.

11. Device according to claim 10, characterized in that said means comprise a ballast (22) at the edge of the curtain (1) opposite to the edge mounted on said shaft (2).

12. A device according to claim 1 or 2, characterized in that the driving wheel is coaxially fixed to the shaft (2) so that it can move at the same angular velocity as the shaft (2).

13. Device according to claim 1 or 2, characterized in that it comprises sliding tracks (5), in which sliding tracks (5) the side edges (4) of the curtain (1) and the control organ (11) are movable parallel to each other.

14. Device according to claim 1 or 2, characterized in that the drive wheel (7) is such that: the control member (11) can be wound helically on the drive wheel about its axis of rotation.

15. A device according to claim 14, wherein the drive wheel (7) has a truncated cone shape such that: the linear speed of the control organ corresponds to the linear speed of the curtain (1) moving between its open position and its closed position, both when the control organ is unwound and when it is wound.

16. Device according to claim 1 or 2, characterized in that a compensator is mounted on said shaft (2) to adapt the peripheral movement of the wound portion of the curtain (1) to the movement of the control organ (11).