Roller curtain device
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 ).
1. A curtain device mounted on a shaft ( 2 ) around which the curtain ( 1 ) may be wound toward an open position and from which it can be unwound toward a closed position, a drive wheel ( 7 ) secured coaxially on the shaft ( 2 ) and cooperating with the curtain ( 1 ) in such a manner so as to move the latter between these two positions, wherein the device comprises a flexible oblong control element ( 11 ) that cooperates with the drive wheel ( 7 ), said control element ( 11 ) being mounted freely in relation to the curtain in such a manner to allow the curtain ( 1 ) to be moved between an open position and a closed position independently of slack which may form in the curtain ( 1 ), on the one hand, and to be able to move along at least one of the side edges ( 4 ) of the curtain ( 1 ) and act on the zone ( 8 ) of the latter opposite that mounted on the shaft ( 2 ), on the other hand, wherein the pitch diameter of the drive wheel ( 7 ) is less than the diameter of the wound portion of the curtain ( 1 ) in its open position, and is greater than the diameter of the aforementioned shaft ( 2 ) or the wound portion of the curtain ( 1 ) in its closed position.
2. The device according to claim 1 , wherein the pitch diameter of the drive wheel ( 7 ) is greater than or equal to half the sum of the diameter of the wound portion of the curtain ( 1 ) in its open position, and of the diameter of the aforementioned shaft ( 2 ) or the wound portion of the curtain ( 1 ) in its closed position.
3. The device according to claim 1 , further comprising means provided to enable a maximum of one coil of the control element ( 11 ) to be wound around the drive wheel ( 7 ) parallel to a plane perpendicular to the axis ( 6 ) of the shaft ( 2 ).
4. The device according to claim 1 , wherein the control element ( 11 ) is incompressible in terms of its length.
5. The device according to claim 1 , wherein the control element ( 11 ) is such that it can exert a pushing force on the curtain ( 1 ) to bring it to its closed position.
6. The device according to claim 1 , wherein the control element ( 11 ) comprises an incompressible element in terms of its length.
7. The device according to claim 1 , wherein the drive wheel ( 7 ) features a series of bosses or indentations ( 9 ) cooperating with the control element ( 11 ) and evenly spaced in relation to one another along the periphery of a circle, the center of which is located on the axis ( 6 ) of the foresaid wheel ( 7 ).
8. The device according to claim 7 , wherein the control element ( 11 ) includes an endless tape or chain.
9. The device according to claim 1 , further comprising means are provided for the curtain ( 1 ) to avoid slack from forming in the latter when it is being unwound.
10. The device according to claim 9 , wherein said means to avoid slack include ballasting ( 22 ) at the edge of the curtain ( 1 ) opposite to that mounted on the aforesaid shaft ( 2 ).
11. The device according to claim 1 , wherein the drive wheel is secured coaxially on the shaft ( 2 ) in such a manner to be able to travel at the same angular speed as this shaft ( 2 ).
12. The device according to claim 1 , further comprising guide rails ( 5 ) in which the side edges ( 4 ) of the curtain ( 1 ) and the control element ( 11 ) can travel parallel to one another.
13. A curtain device mounted on a shaft ( 2 ) around which the curtain ( 1 ) may be wound toward an open position and from which it can be unwound toward a closed position, a drive wheel ( 7 ) secured coaxially on the shaft ( 2 ) and cooperating with the curtain ( 1 ) in such a manner so as to move the latter between these two positions, wherein the device comprises a flexible oblong control element ( 11 ) that cooperates with the drive wheel ( 7 ), said control element ( 11 ) being mounted freely in relation to the curtain in such a manner to allow the curtain ( 1 ) to be moved between its open position and its closed position independently of the slack which may form in the curtain ( 1 ), on the one hand, and to be able to move along at least one of the side edges ( 4 ) of the curtain ( 1 ) and act on the zone ( 8 ) of the latter opposite that mounted on the shaft ( 2 ), on the other hand, wherein the drive wheel ( 7 ) is such that the control element ( 11 ) can be wound spirally on it around its axis of rotation.
14. The device according to claim 13 , wherein the drive wheel ( 7 ) has a truncated conical form such that, during both unwinding and winding of the control element, the linear speed of the latter essentially corresponds to that of the curtain ( 1 ) traveling between its open position and its closed position.
15. The device according to claim 1 , further comprising a compensator is mounted on the aforementioned shaft ( 2 ) enabling the wound portion of the curtain ( 1 ) to be adapted to the travel of the control element ( 11 ).