Folding door

Abstract

 A folding door (1) comprising two jambs (2) that are mutually connected in an upper region by a lintel (3) that contains first means (7) for lifting a screen (4), the screen being extendable approximately vertically between the pair of jambs by means of a plurality of stiffening tubes (5) arranged approximately horizontally, sleeves (18) provided with seats (25) for one or more fixed guiding cables (26,27) being slidingly associated with the ends of the tubes (5).

Description

[0001] The present invention relates to a folding door particularly for industrial applications.

[0002] Currently it is known to manufacture folding doors that are usually constituted by two jambs that are connected to each other in an upper region by a supporting lintel for appropriately provided means that are suitable to move a screen that can be extended approximately vertically between said pair of jambs and is connected to said lintel with its upper side.

[0003] Such movement means generally comprise a drum that has a horizontal axis for winding and unwinding appropriately provided motion transmission belts that are in turn connected to the screen.

[0004] A plurality of stiffening rods are usually associated or monolithic with the screen and are arranged horizontally at a preset mutual distance so as to divide said screen into a plurality of flaps or sectors arranged consecutively one above the other.

[0005] Each belt is connected to the lower stiffening rod of the screen with one of its ends and to the horizontal-axis drum with its opposite end; each belt, moreover, passes through supporting rings, which are provided in one or more preset stiffening rods and are arranged along vertical rows at a preset mutual distance depending on the folding pitch to be given to the screen.

[0006] In this manner, the gradual synchronous winding or unwinding of the belts on the horizontal-axis drum is matched respectively by the packing of the various flaps or sectors of the screen proximate to the upper part of the door or by its extension along a substantially vertical plane to the base of said door, so as to close it.

[0007] Approximately vertical guiding means are usually associated or monolithically coupled at the inner lateral surfaces of the pair of jambs, which therefore face each other, in order to slidingly accommodate suitable wheeled carriages provided at the ends of the stiffening rods, so as to keep the screen coupled to the pair of jambs during its approximately vertical movement.

[0008] EP-0 591 050 is known in this regard and discloses a folding door provided with a flexible screen that is connected laterally to guiding means associated with the respective jambs.

[0009] Such guiding means are constituted by vertical rails at which carriages are coupled slidingly; said carriages are in turn associated with the ends of suitable tubular stiffening elements that are connected to the screen horizontally.

[0010] At least one of the two carriages associated with a single tubular stiffening element is connected to the respective end thereof by way of an articulation whose axis is constituted by a pivot that is designed to yield when a preset level of stress affects the screen, so as to prevent any damage or breakage thereof.

[0011] The main drawback of these known kinds of folding door is that for example due to possible gusts of wind, the continuous swelling undergone by the screen and therefore the corresponding flexing imparted to the rods cause damaging stresses or pulsed percussions that are discharged between the rails and the carriages, with consequent deformations or distortions of the former and very rapid deterioration of the bearings of the latter.

[0012] This leads to a double drawback: in a first case, the door can be susceptible of malfunctions due to an alteration of the guiding path imposed by the rails, thus deformed, to the carriages; in a second case, damage of such extent as to trigger breakages of components of the door can occur.

[0013] Another drawback is that even in the absence of wind, the bearings of the carriages, as well as the rails, are susceptible, during mutual sliding, of rapid wear as a consequence of the excessive friction that occurs between them, for example due to possible infiltrations of impurities and/or dirt.

[0014] Another drawback is that the presence of the carriages affects considerably the total load that bears on the motors and on the mechanical transmission elements, such as for example the pulleys and bearings.

[0015] Another drawback is that high maintenance costs are required due to periodic replacements of the bearings of the carriages or to any operations for cleaning and lubricating the rails.

[0016] Another important drawback of the prior art is that the carriages are rigidly connected to the ends of the respective rods and this, in addition to further stiffening a structure that is per se scarcely flexible, also makes it troublesome to install the screen between the two jambs.

[0017] The aim of the present invention is to solve the above-noted problems, eliminating the drawbacks of the prior art, by providing a folding door that is particularly flexible and therefore allows to obtain a damping effect for example on the oscillations induced by gusts of wind, so as to avoid being susceptible of consequent possible damage or breakage.

[0018] Within this aim, an object of the present invention is to provide a folding door whose mechanical components are reliable over time and interact with each other so as to be scarcely subject to wear.

[0019] Another object of the invention is to provide a folding door that allows to achieve a reduced weight of its parts assigned to movement, so as to avoid overloading the power supply motors and/or the transmission elements.

[0020] Another object is to provide a folding door that can be assembled easily and has particularly low maintenance costs.

[0021] Another object is to provide a folding door that by allowing easy and rapid installation can also be used in a versatile manner for various applications.

[0022] Another object is to provide a folding door that is structurally simple and has low manufacturing costs.

[0023] This aim and these and other objects that will become better apparent hereinafter are achieved by a folding door comprising two jambs that are mutually connected in an upper region by a lintel that contains first means for lifting a screen, said screen being extendable approximately vertically between said pair of jambs by means of a plurality of stiffening tubes arranged approximately horizontally, characterized in that sleeves provided with seats for one or more fixed guiding cables are slidingly associated with the ends of said tubes.

[0024] Further characteristics and advantages of the present invention will become better apparent from the following detailed description of a particular but not exclusive embodiment thereof, illustrated by way of nonlimiting example in the accompanying drawings, wherein:

Figures 1 and 2 are front perspective views of a folding door in the open and closed positions;

Figures 3 and 4 are respectively a front view and a perspective view of a detail of the folding door in the closed position;

Figure 5 is a sectional view of the folding door, taken along the line V-V of Figure 1;

Figure 6 is a sectional view of the folding door, taken along the line VI-VI of Figure 2;

Figure 7 is an exploded perspective view of a bush that is associable with a sleeve that is connected to the end of a stiffening tube for a screen;

Figure 8 is a perspective view of a cable that passes through a seat formed transversely with respect to the sleeve connected to the end of the respective screen stiffening tube.

[0025] In the embodiments that follow, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other embodiments.

[0026] With reference to the figures, the reference numeral 1 designates a folding door that comprises a supporting frame composed of a pair of lateral jambs, generally designated by the reference numeral 2, which are connected to each other in an upper region by a lintel 3.

[0027] The upper side of a screen 4 is connected to the lintel 3 and can be extended approximately vertically between the two jambs 2; a plurality of stiffening tubes 5 are associated with said screen, are at least partially hollow and are arranged approximately horizontally; the tubes have a length that advantageously slightly exceeds the entire transverse dimension of the screen 4.

[0028] The stiffening tubes 5 are arranged at a preset vertical distance from each other and lie at suitable seats or pockets formed in the screen 4, which is thus divided into a plurality of mutually consecutive sectors, generally designated by the reference numeral 6.

[0029] The lifting and lowering of the screen 4 between the pair of jambs 2 is allowed by way of appropriately provided first movement means, generally designated by the reference numeral 7, which are supported and accommodated in the lintel 3.

[0030] Such first movement means 7 comprise a rotating drum 8 that has a horizontal axis for the winding and unwinding of one or more actuation belts, generally designated by the reference numeral 9, which are fixed with one of their ends to the rotating drum 8 and with their other end to the stiffening tube 5, which is adjacent to a lower edge 10 of the screen 4 or to a separate rod-like end element, designated by the reference numeral 11.

[0031] The actuation belts 9 pass through suitable supporting rings, generally designated by the reference numeral 12, which are associated or monolithic with one or more of the stiffening tubes 5, so as to be arranged along one or more substantially vertical parallel rows.

[0032] In the illustrated embodiment, the supporting rings 12 that belong to a same vertical row are alternately present at sequential stiffening tubes 5.

[0033] In addition to the actuation belts 9, the upper end of at least one compensation belt 13 is also connected to the rotating drum 8 and is optionally guided by means of a pulley 14 that is associated with the lintel 3, which is connected at the lower end to a counterweight 15 that is arranged within at least one of the jambs 2.

[0034] At the tips, designated by the reference numeral 16, of the stiffening tubes 5 first axial cavities 17 are therefore provided in which respective sleeves, generally designated by the reference numeral 18, are associated at least partially slidingly and axially.

[0035] In greater detail, the sleeves 18 are constituted by a cylindrical and hollow head 19 that protrudes axially with respect to an adjacent stem 20, which is also cylindrical but has a smaller outside diameter than the head 18.

[0036] Optionally, the relative sliding between the stiffening tubes 5 and the respective stems 20 of the sleeves 19 can be controlled preferably by connecting them to suitable second elastically deformable return means, such as springs, which are not shown.

[0037] The heads 19 have second axial cavities 21 that are cylindrical and whose axis coincides with the axis of the first axial cavities of the respective stiffening tubes 5.

[0038] Two first holes, generally designated by the reference numeral 22, are formed on the outer lateral surface of each head 19 along a diametrical axis and approximately halfway along the length of said head.

[0039] Respective substantially cylindrical bushes, designated by the reference numeral 23, can be associated with the heads 19 of the sleeves 18 and have, approximately halfway along their length, a second diametrical hole 24, whose axis coincides with a diameter of the corresponding transverse cross-section of said bushes.

[0040] The bushes 23 have approximately the same length as the heads 19 and a diameter that is slightly smaller than the diameter of the second axial cavities 21.

[0041] In this manner, the seating of the bushes 23 within the respective second axial cavities 21 makes it possible to align vertically each pair of first holes 22 and the second hole 24, so as to form seats 25 for the passage of one or more fixed guiding cables.

[0042] In the particular embodiment described, a first approximately vertical rear cable 26 and an adjacent likewise vertical second front cable 27 are provided within each jamb 2.

[0043] The first rear cable 26 and the second front cable 27 are rigidly coupled, preferably by interposing third adjustable pretensioning means, generally designated by the reference numeral 28, to the lower base, designated by the reference numeral 29, of the jambs 2 and to a region 30 for connection to the lintel 3.

[0044] With reference to Figures 1, 2, 3 and 4, in the particular embodiment described the heads 19 of the sleeves 18 connected to the stiffening tubes 5 provided with the supporting rings 12 are associated with the second front cable 27, and so are the two heads 19 that correspond to the stiffening tube 5 on which the free ends of the actuation belts 9 are fixed.

[0045] The heads 19 of the sleeves 18 connected to the other stiffening tubes 5 are instead associated with the first rear cable 26, while the heads of the rod-like end element 11 are free.

[0046] This entails that during the winding of the actuation belts 9 on the rotating drum 8, the stiffening tube 5 to which the free ends of the belts are fixed is raised by them, drawing upward the lower edge 10 connected to the rod-like element 11 and moving gradually toward the next stiffening tube 5 that is associated with the second front cable 27.

[0047] As the winding of the actuation belts 9 on the rotating drum 8 gradually advances, the heads 19 of the sleeves 18 associated with the second front cable 27 push each other upward as a consequence of the gradual packing or adjacent arrangement of the respective sectors 6 that are mutually consecutive.

[0048] This entails that the sectors 6, in addition to moving toward each other, also undergo a successive tensioning, which produces the sequential traction of the heads 19 of the sleeves 18 associated with the first rear cable 26.

[0049] Once the winding of the actuation belts 9 has been completed, the screen 4 is completely raised and the sectors 6 are mutually packed in the upper region of the door 1 adjacent to the lintel 3, so as to achieve its open position.

[0050] The complete lifting of the screen 4 is matched by the arrangement of the upper stiffening tube 5 of the second front cable 27 so that the heads 19 of the respective sleeves 18 are adjacent to the stroke limiter of the second front cable 27, so that the underlying heads 19 associated therewith are arranged in contact with each other.

[0051] Likewise, the stiffening tubes 5 of the first rear cable 26 have respective sleeves 18 with heads 19 arranged in contact with each other at a lower height than the heads 19 associated with the second front cable 27.

[0052] It has thus been found that the invention has achieved the intended aim and objects, a folding door having been provided which, thanks to the flexibility provided by the presence of the fixed cables with which the sleeves are slidingly associated, said sleeves being in turn slidingly connected to the ends of the respective stiffening tubes, allows to obtain a damping effect for example on the oscillations induced by gusts of wind, so as to avoid being susceptible of consequent possible damage or breakage.

[0053] It is also evident that the folding door, in addition to having a reduced weight of its parts intended for movement, so as to avoid overloading the motors and/or the transmission elements, is particularly reliable over time, also thanks to the fact that the mutual sliding between the cables and the seats that are provided in the sleeves allows to avoid the onset of evident wear.

[0054] The invention is of course susceptible of numerous modifications and variations, all of which are within the scope of the appended claims.

[0055] The materials used, as well as the dimensions that constitute the individual components of the invention, may of course be more pertinent according to requirements.

[0056] The various means for performing certain different functions need not certainly coexist only in the illustrated embodiment but can be present per se in many embodiments, including ones that are not illustrated.

[0057] The characteristics that are indicated as advantageous, convenient or the like may also be omitted or replaced with equivalents.

[0058] The disclosures in Italian Utility Model Application No. TV2003U000014 from which this application claims priority are incorporated herein by reference.

[0059] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A folding door comprising two jambs that are mutually connected in an upper region by a lintel that contains first means for lifting a screen, said screen being extendable approximately vertically between said pair of jambs by means of a plurality of stiffening tubes arranged approximately horizontally, characterized in that sleeves provided with seats for one or more fixed guiding cables are slidingly associated with the ends of said tubes.

2. The door according to claim 1, wherein the upper side of said screen is connected to said lintel, said screen being extendable approximately vertically between said pair of jambs by way of said stiffening tubes, which are arranged at a preset vertical distance from each other and lie at appropriately provided seats or pockets formed in said screen, which is thus divided into a plurality of sectors, characterized in that first axial cavities are formed at the ends of said stiffening tubes, which are at least partially hollow, and said sleeves are associated at least partially slidingly and axially within said first axial cavities.

3. The door according to claims 1 and 2, wherein said first lifting means are supported and/or accommodated in said lintel and comprise a rotating drum having a horizontal axis for winding and unwinding one or more actuation belts which are fixed with one of their ends to said rotating drum and with their other end to the stiffening tube that is adjacent to the lower edge of said screen or to a separate rod-like end element, characterized in that said sleeves are constituted by a cylindrical and hollow head that protrudes axially with respect to an adjacent stem that is also cylindrical and has a smaller outside diameter than said head.

4. The door according to claims 1 and 3, wherein said actuation belts pass through appropriately provided supporting rings that are associated or monolithic with one or more of said stiffening tubes so as to be arranged along one or more substantially vertical parallel rows, characterized in that the supporting rings that are part of a same row are alternately present at said mutually sequential stiffening tubes.

5. The door according to claims 1, 3 and 4, characterized in that it comprises second elastically deformable return means for controlling the sliding of said stems of said sleeves within said first axial cavities of said stiffening tubes.

6. The door according to one or more of the preceding claims, characterized in that said heads of said sleeves have second cylindrical axial cavities whose axis coincides with the axis of said first axial cavities of said stiffening tubes.

7. The door according to claims 1 and 6, characterized in that two first holes are formed on the outer lateral surface of each one of said heads along a diametrical axis and approximately halfway along its length.

8. The door according to one or more of the preceding claims, characterized in that respective substantially cylindrical bushes are associated with said heads of said sleeves, their diameter being slightly smaller than the diameter of said second axial cavities and their length being approximately equal to the length of said heads.

9. The door according to one or more of the preceding claims, characterized in that said bushes have, approximately halfway along their length, a second diametrical hole, so that the seating of said bushes within said second cavities allows to align vertically each pair of said first holes and said second hole, so as to form seats for the passage of said one or more fixed guiding cables.

10. The door according to one or more of the preceding claims, characterized in that inside each one of said jambs there is an approximately vertical first rear cable that is adjacent to a second likewise vertical front cable.

11. The door according to one or more of the preceding claims, characterized in that said first rear cable and said second front cable are coupled, by way of the interposition of third adjustable pretensioning means, to the lower base of said jambs and to the region for connection to said lintel.

12. The door according to one or more of the preceding claims, characterized in that the heads of the sleeves connected to the stiffening tubes provided with said supporting rings are associated with said second front cable and so is the pair of heads that correspond to the stiffening tube on which the free ends of said actuation belts are fixed.

13. The door according to one or more of the preceding claims, characterized in that the heads of said sleeves that are connected to the remaining said stiffening tubes are associated with said first rear cable.

14. The door according to one or more of the preceding claims, characterized in that the heads of said rod-like end element are free.

15. The door according to one or more of the preceding claims, characterized in that it comprises elastically deformable return means for controlling the sliding of said stems of said sleeves within said first axial cavities of said stiffening tubes.

Drawing