Roller shutter with automatic locking in closing position

Abstract

 Roller shutter comprising a roller gate (1), a revolving axle (2) to which the roller gate (1) is connected by chain connection means (5) which allow the winding of the roller gate (1) about the revolving axle (4), and an electric motor (40) or other means to control the rotation of the revolving axle (4). The chain connection means (5) are formed by segments (9, 13) which are hingedly connected to rotate with respect to each other of a very little angle and braking means (41) for the revolving axle are provided which co-operate with the chain connection means (5) in order to prevent a lifting of the roller shutter (1) by forces acting from the bottom.

Description

[0001] The present invention relates to a roller shutter with automatic locking in closing position.

[0002] Roller shutters are known used for closing windows or other different room openings. Particularly roller shutters are known formed by strips of alluminium, wood or plastic and which are placed in succession with articulated connection so that they can be wound about revolving axles placed on the top of the room opening. Such revolving axles are operated usually by electric motors, little winches or belts which allow the axle rotation and consequently the unwinding or the winding of the roller shutter that is sliding vertically.

[0003] During the room closing and consequently the roller shutter unwinding, the roller shutter is lowered so that its inferior side is at contact with the ground. However, an undesirable operator can force the roller shutter from the outside and thrusting up the roller shutter he can get in the room. In order to solve this problem more or less complex or efficient locking devices of the roller shutter are provided.

[0004] In view of the state of the art described, it is an object of the present invention to form a roller shutter with automatic locking in closing position.

[0005] According to the present invention, such object is attained by a roller shutter comprising a roller gate, a revolving axle to which said roller gate is connected by chain connection means which allow the winding of said roller gate about said revolving axle, and means to control the rotation of said revolving axle, characterized in that said chain connection means are formed by segments which are hingedly connected to rotate with respect to each other of very little angles and braking means for said revolving axle are provided which co-operate with said chain connection means in order to prevent a lifting of said roller gate by forces acting from the bottom.

[0006] Thanks to the present invention it is possible to form a roller shutter that is automatically locked in closing position, so that anybody cannot lifts the roller gate from the outside and get in the room.

[0007] The features and the advantages of the present invention will be made evident by the following detailed description of a particular embodiment, illustrated as not limiting example in the annexed drawings, wherein:

Figure 1 is a perspective view of the roller shutter according to the embodiment of the invention;

Figure 2 is a more detailed perspective view of a particular of figure 1;

Figure 3 is similar to figure 2, but with wound chain;

Figure 4 is a lateral view of a chain connection device interposed between the roller gate and the revolving axle of the roller shutter of figure 1, in state of total axle unwinding;

Figure 5 is a similar to figure 4 but with wound chain.

[0008] In figure 1 is described a roller shutter comprising a roller gate 1 formed by alluminium strips 2 which are hingedly connected and can slide in the guides 3. Such roller gate is connected to an octagonal section revolving axle 4 by two connection devices 5 formed by two chains 6 fixed at the bottom to the roller gate 1 and at the top to respective couples of octagonal rings 7 which are integral with the revolving axle 4, in turn hinged at 8 to the walls of the room opening which are not shown in figure 1.

[0009] The chain 6 of the connection device 5, described in more detail in the perspective view of figure 2 and in the lateral view of figure 4, comprises a terminal segment 9 connected to the first strip 2 of the roller gate 1 by the hooking of its curve portion 10, which forms a internal cavity 11, with a hook portion 12 of the strip 2. The terminal segment 9 is connected to a adjacent segment 13 of the chain, which is more narrow than the segment 9, by a hook portion 14 of an extension 15 of the superior side of the segment 9, which is inserted in a circular cavity 16 of the inferior side of the segment 13 so that it can rotate only of a little angle with respect to the segment 9. In fact the space 30 that is between an extremity of the cavity 16 of the inferior side of the segment 13 and the extension 15, when the other extremity of the cavity 16 is at contact with the extension 15, is very little. This allows the segments 9 and 13 to rotate only of an angle substantially of about 30°. The segment 13 is the first one of a series of equal segments which are connected with each other by hook portions 14 as that before described. Each segment 13 shown a U-shaped central portion 17 to which a separable rubber insert 18 is connected and in the cavity 19 of which a bolt 20 is engaged which also passes through holes of laminas 21.

[0010] The last and the next to last superior segment 13 of the chain 6 are fixed to the couple of octagonal rings 7 by a bolt 22 which engages in a cavity 23 of the extension 15 of the next to last segment, engaged in the hook portion 14 with the last segment, and in a cavity 14 of a portion 25 of a side of said octagonal rings 7. The portion 25 shows others cavities 26 and 27 in correspondence of the cavities 19 and 23 of the last segment 13 of the chain 6, in which suitable bolts can engage in order to allow a more efficient connection of the couple of rings 7 to the chain 6. Each of the octagonal rings 7 shows a portion 70 where a transversal hole is provided in which a bolt 28 engages in order to fix the position of the rings 7 in the revolving axle 4.

[0011] With the wound chain 6 as described in figures 3 and 5, the roller shutter 1 is wound about the axle 4, as shown in figure 5. Then the operation of a electric motor 40 accommodated inside the axle 4 and having a braking device 41, the axle 4 can be made rotate counterclockwise (showing figure 5) and the roller shutter and the chain 6 are unwound so that the inferior last strip 2 of the roller gate 1 is at contact with ground. At this point a suitable automatism, which is not shown in figures, allows the braking and the stop of the electric motor 40 which so does not allow rotating to the axle 4. If an operator exercises a thrust from the bottom to the top on the roller gate 1, the blocking device intervenes formed by the connection device 5 and the braking device 41 of the electric motor 40. In fact the hook of the first strip 2 inside of the cavity 11 of the first segment 9 exercises a thrust to the top on the same segment and on the remaining part of the chain 6, and this, joining with the immobility of the revolving axle 4, allows a major curving of the same chain. In the hooking portions 14 of the segments 9 and 13 the extension 15 can rotate inside the circular cavities 16 only of a little angle, so that the roller gate can be lifted only in minimum part insufficient for the entry of a person from the outside of the room. The blocking of the roller gate 1 does not prevent its successive rewinding by rotation of the revolving axle 4, which is controlled by the electric motor by means of a suitable pulse from the designated operator.

Claims

1. Roller shutter comprising a roller gate (1), a revolving axle (2) to which said roller gate (1) is connected by chain connection means (5) which allow the winding of said roller gate (1) about said revolving axle (4), and means (40) to control the rotation of said revolving axle (4), characterized in that said chain connection means (5) are formed by segments (9, 13) which are hingedly connected to rotate with respect to each other of a very little angle and braking means (41) for said revolving axle are provided which co-operate with said chain connection means (5) in order to prevent a lifting of said roller gate (1) by forces acting from the bottom.

2. Roller shutter according to claim 1, characterized in that said chain connection means (5) comprising at least a couple of chains (6).

3. Roller shutter according to claim 2, characterized in that said segments (9, 13) are hingedly connected by means of hooking portions (14) each of which is formed by an extension (15) of a superior side of one of said segments (13) of the chain (6) which engages in a cavity (16) of an inferior side of a successive one of said segments (13).

4. Roller shutter according to claim 3, characterized in that the rotations of said very little angles between said segments (9, 13) of said chain connection means (5) are due to very little spaces (30) each of which is between an extremity of said cavity (16) of said inferior side of one of said segments (13) and said extension (15) of said superior side of one of said segments (13), when the other extremity of said cavity (16) is at contact with said extension (15).

5. Roller shutter according to claim 4, characterized in that said very little angles are substantially of 30°.

6. Roller shutter according to claim 5, characterized in that laminas (21) are provided in succession and placed at the sides of said segments (13) of the chain (6), said laminas (21) being provided with holes so that suitable bolts (20) engage both said holes of said laminas (21) and central cavities (19) of said segments (13).

7. Roller shutter according to claim 2, characterized in that couples of rings (7) are provided which are hooked to each chain (6) and are integral with said revolving axle (4).

8. Roller shutter according to claim 6, characterized in that said revolving axle (4) has a polygonal section and said segments (13) of the chain (6) have a length substantially equal to a side of said polygonal section.

Drawing