The present invention relates to an industrial door.

To close openings made through the masonry structure of an industrial shed, it is known to provide a door of the type comprising a plurality of vertical leaves that are slidably coupled or hinged to one another, a substantially horizontal guide fixed to the masonry structure above the leaves, and a conveying carriage, which is connected to one of the two end leaves, and is engaged to a chain conveyor for performing rectilinear displacements along the guide and displacing the leaves between an opening position and a closing position of the industrial door.

Generally, the chain conveyor is wound to form an endless loop about a pair of sprocket wheels mounted so as to turn about respective longitudinal axes under the thrust of an electric motor fixed to the masonry structure on the outside of the guide of the conveying carriage.

Known industrial doors of the above type have some drawbacks principally resulting from the fact that the chain conveyor is relatively noisy, involves frequent maintenance interventions, and is relatively cumbersome on account of the installation of the aforesaid electric motor on the masonry structure and on the outside of the guide of the conveying carriage.

Document DE 19932891 A1 relates to an industrial door comprising at least one leaf and actuator means for displacing the leaf between an opening position and a closing position of the industrial door itself. The actuator means comprise a carriage for advance of the leaf, a guide for guiding the carriage, and actuator means for advance of the carriage along the guide and in a given direction. The actuator means are carried by the carriage and comprise a motor mounted on the carriage for displacing the carriage itself along the guide.

It is an object of the present invention to provide an industrial door designed to eliminate the aforementioned drawbacks and that will be simple and inexpensive to produce.

According to the present invention, there is provided an industrial door as claimed in the accompanying claims.

The present invention will now be described with reference to the accompanying drawings, which illustrates a non-limiting example of embodiment thereof and in which:

• Figure 1 is a schematic side view, with parts enlarged for reasons of clarity, of a preferred embodiment of the industrial door of the present invention;
• Figures 2 and 3 are two schematic perspective views of a detail of the industrial door of Figure 1;
• Figure 4 illustrates, in schematic perspective view, with parts enlarged for reasons of clarity, the industrial door of Figure 1 in two different operating positions; and
• Figure 5 is a schematic perspective view of a variant of the industrial door of Figure 1.

With reference to Figure 1, designated as a whole by 1 is a door mounted to close an opening 2 made through the masonry structure 3 of an industrial shed.

The door 1 comprises a plurality of vertical plane leaves 4 (in the case in point, four leaves 4), which have a substantially rectangular shape, are hinged together in points corresponding to respective longitudinal edges parallel to a vertical direction 5 so as to turn, with respect to one another and according to modalities that will be illustrated in greater detail in what follows, about corresponding axes 6 of fulcrum parallel to the direction 5, and comprise a first end leaf 4 (hereinafter designated by 4a), hinged to the structure 3 so as to turn, with respect to the structure 3, about an axis 7 of fulcrum parallel to the axes 6, a second end leaf 4 (hereinafter designated by 4b), opposite to the leaf 4a, and two intermediate leaves 4 (hereinafter designated by 4c), arranged between the leaves 4a and 4b.

The door 1 moreover comprises a guide 8, which has an elongated shape, extends above the leaves 4 in a horizontal direction 9 transverse to the direction 5, and is defined by a tubular sectional element 10, which is fixed to the structure 3 above the opening 2, is substantially U-shaped with its concavity facing downwards, and comprises two longitudinal edges bent so as to define two horizontal plane tracks 11, set parallel to one another and to the direction 9.

According to what is illustrated in Figures 2 and 3, the leaves 4 are mobile between a closing position (Figure 1) and an opening position (Figure 4b) of the opening 2 under the thrust of a conveying device 12 comprising a carriage 13, which is mounted within the guide 8 and comprises, in turn, a supporting frame 14 provided with two mutually parallel axles 15, 16, each of which is coupled in a rotatable way to the frame 14 so as to turn, with respect to the frame 14 itself, about a longitudinal axis 17 thereof parallel to a horizontal direction 18 orthogonal to the directions 5 and 9, and carries fitted to its ends two wheels 19 engaged in the two tracks 11.

The axle 15 is set in rotation about it own axis 17 by an actuator device 20 comprising an electric motor 20a, which is mounted on the frame 14 and has an output shaft defined by a screw 21, which extends parallel to the direction 9, and meshes with a helical gear 22, fitted on a supporting shaft 23 parallel to the direction 18. The shaft 23 is mounted in a coaxial position facing a transmission shaft 24 coupled, normally, in an angularly fixed way to the shaft 23 itself via the interposition of a clutch 25, in the case in point a clutch of an electrical type.

The shaft 24 sets in rotation the axle 15 via a chain 26 of gears comprising a first gear 27a fitted on the shaft 24 and a second gear 27b fitted on the axle 15 and coupled to the gear 27a itself.

The carriage 13 is connected to the leaf 4b via a dragging rod 28, which extends downwards from the carriage 13, has a longitudinal axis 28a parallel to the direction 5, is coupled in a rotatable and axially slidable way, in a position corresponding to a bottom end thereof, to an outer longitudinal edge of the leaf 4b, and is provided with a substantially parallelepipedal top bushing 29, which is fixed to a top end of the rod 28 in a direction transverse to the axis 28a and is slidably coupled to a guide 30 made in the frame 14 parallel to the direction 9.

The bushing 29 is moreover coupled via a screw/nut screw coupling, to a screw 31 of a corresponding actuation device 32, which defines part of the conveying device 12 and comprises an electric motor 33, which is mounted on the frame 14 and has an output shaft 34 opposite to the screw 21 of the motor 20a. The shaft 34 extends parallel to the direction 9 and is connected to the screw 31 via a belt transmission 35 of a known type for setting the screw 31 in rotation and imparting upon the bushing 29, and hence upon the rod 28, rectilinear displacements along the guide 30 in the direction 9.

Each electric motor 20a, 33 is supplied via a corresponding electrical-sliding-contact supply device 36 comprising a plurality of guides 37 made of conductive material (in the case in point, two guides 37) fixed within the sectional element 10 parallel to the direction 9, and a plurality of electrical contacts 38, which are also made of conductive material, are equal in number to the corresponding guides 37, project upwards from the corresponding motor 20a, 33, and are designed to engage slidably the corresponding guides 37 during advance of the carriage 13 along the guide 8.

Operation of the door 1 will now be described with reference to Figures 1 and 4 starting from an instant in which:

• the leaves 4 are arranged in their closing position of the opening 2 (Figure 1);
• the two motors 20a, 33 are deactivated; and
• the bushing 29 is set in a point corresponding to one end of the guide 30 adjacent to the axle 16 (Figures 1-3 and 4a).

To open the door 1, the carriage 13 is displaced along the guide 8 via the actuation device 20 so that, by combining the displacement of the carriage 13 in the direction 9 with the rotation of the leaves 4a, 4b, and 4c about the corresponding axes 6, 7, and 28a, the leaves 4a, 4b, and 4c will be folded substantially in contact with one another (Figure 4a). Proper rotation of the leaves 4a, 4b, and 4c about the corresponding axes 6, 7, and 28a is guaranteed by a guide device (of a known type and not illustrated), which comprises a shaped guide projecting laterally from the guide 8 and, for each leaf 4a, 4b, and 4c, a corresponding roller designed to engage the shaped guide itself.

When the carriage 13 reaches the end of the guide 8, the encumbrance of the carriage 13 itself in the direction 9 prevents complete and proper folding of the leaf 4b in contact with the adjacent leaf 4c (Figure 4a). Folding of the leaf 4b, and hence opening of the door 1, is completed by activating the electric motor 33 so as to displace the bushing 29, and hence the dragging rod 28, between the ends of the guide 30 in the direction 9 (Figure 4b).

When the bushing 29 reaches the end of the guide 30 adjacent to the axle 15, completing folding of the leaf 4b, the motor 33 is deactivated in response to a signal coming from a sensor 39 (Figure 1) fixed to the structure 3 for detecting complete opening of the door 1.

To close the door 1, the carriage 13 is displaced along the guide 8 via the actuation device 20 so that, by combining the displacement of the carriage 13 in the direction 9 with the rotation of the leaves 4a, 4b, and 4c about the corresponding axes 6, 7, and 28a, the leaves 4a, 4b, and 4c set themselves in a position substantially coplanar to one another.

When the carriage 13 reaches the end of the guide 8, the encumbrance of the carriage 13 itself in the direction 9 prevents complete and proper closing of the leaf 4b in contact with the structure 3. Closing of the leaf 4b, and hence of the door 1, is completed by activating the electric motor 33 so as to displace the bushing 29, and hence the dragging rod 28, between the ends of the guide 30 in the direction 9.

When the bushing 29 reaches the end of the guide 30 adjacent to the axle 16, thus completing closing of the leaf 4b, the motor 33 is deactivated in response to a signal coming from a sensor 40 (Figure 1) fixed to the structure 3 for detecting complete closing of the door 1.

The door 1 thus presents a number of advantages principally resulting from the fact that:

• the entire actuation device 20 of the carriage 13 is mounted directly on the carriage 13 itself, has relatively small overall dimensions, and is relatively quiet;
• the actuation device 32 of the dragging rod 28 of the leaf 4b guarantees a complete and proper opening and closing of the door 1, in particular when the conformation of the opening 2 prevents installation of a guide 8 having a length, measured parallel to the direction 9, greater than the width of the opening 2, which is also measured parallel to the direction 9; and
• the clutch 25 enables, in the case of absence of supply of the motor 20a, decoupling of the shafts 23 and 24 from one another and manual displacement of the carriage 13 along the guide 8.

The variant of Figure 5 differs from what is illustrated in the preceding figures only for the fact that, therein, the leaves 4a, 4b, and 4c are eliminated and replaced, in the case in point, with a single slidable leaf 4, which can move in the direction 9 between a closing position (illustrated with a solid line in Figure 5) and an opening position (illustrated with a dashed line in Figure 5) of the opening 2.