The present invention relates to fast roll-up doors comprising a curtain having lateral edges which are coupled to guiding rails for guiding the curtain during winding and unwinding thereof about a winding axle. In particular, said lateral edges are resilient to afford a reversible deformation of the curtain upon exposure to a pressure applied transverse to the plane defined by the curtain, such as wind or an impact with a vehicle or similar.
There are many types of shutting systems for closing a bay, separating a room or covering a swimming pool, etc. Fast roll-up doors comprise a flexible curtain suitable for being wound or unwound about a winding axle at high speed, allowing apertures of large dimensions to be opened and shut in a very short time. They are particularly suitable for closing apertures between two rooms or between a room and the outside in warehouses, workshops, shops, laboratories, and the like. In order to ensure structural stability, the lateral edges of such curtains are coupled to guiding rails fixed to the lateral walls defining the lateral edges of the aperture. The lateral edges of the curtain can freely slide along the guiding rails during winding and unwinding but are held by the rails unless exposed to an unexpected force of sufficient magnitude to de-couple the curtain edges from their corresponding guiding rails. Some doors are provided with means for automatically driving the pulled-out curtain edge back into the rail. Such re-insertion system is disclosed e.g., in WO2008155292.
Such roll-up doors can be exposed to many aggressions, such as wind (in case they separate indoor from outdoor), accumulated rain and snow (in case the curtain is not held vertically); vehicles in movement, static obstacles placed in the closing trajectory of the curtain, and the like. Because such roll-up doors may have rather large dimensions, even a moderate pressure applied on one side of the curtain, such as by wind, can generate forces of high magnitude which are transmitted to the lateral edges of the curtain and to the coupling between lateral edges and guiding rails. As a consequence, friction between the lateral edges of the curtain and the guiding rails may be created thus hindering the winding and unwinding speed of the curtain and increasing wear rate. The guiding rails in which the lateral edges of the curtain move and are held, can be subjected to very uneven forces at one side of the curtain compared with the other side. It may even happen that all the forces thus generated are concentrated on a single side of the curtain, thus creating torsion on certain parts of said guiding rails, resulting in unpleasant appearance of crease in the curtain and in irregular wear both of the guiding rails and of the lateral edges of the curtain. Moreover, such uneven distribution of the forces increases the risk of said lateral edges suddenly coming free of the guiding rails. Even with a re-insertion system as discussed above, de-coupling of a lateral edge of a curtain is as far as possible to be avoided as it may damage it as a result.
In order to evenly distribute the forces generated by a pressure applied onto the curtain, WO9220895 proposes to elastically mount the guiding rails on static supports solidly fixed to the walls defining the lateral edges of the aperture. In a particular embodiment, the guiding rails are coupled to said static supports by means of a series of rods distributed along the length of the guiding rails, said rods being oriented normal to both guiding rails and static support, and being provided with resilient means, such as a helicoidal spring, allowing the guiding rails to reversibly separate from the static supports upon application of a given force. This solution successfully distributes the forces over the whole length of both lateral edges of the curtain and maintains the curtain under moderate tension, thus avoiding the concentration of forces at one particular area of the curtain and thus avoiding the formation of a wavy and uneven curtain surface. The installation of such system is, however, quite labour intensive, as the rods with resilient means must be mounted and calibrated individually and coupled to both guiding rails and static support. It also requires special means for sealing the space created between the static support and the guiding rails as the latter are being separated from the static support (cf. skirt (12) in FIG. 2 of WO9220895). These elements have a negative impact on the cost of the roll-up door system. Furthermore, noise is generated by the sliding of metal rods through holes in the metal static support as the springs are being strained. The noise can be reduced by using foam or elastomeric materials as illustrated in FIGS. 4 and 5 of WO9220895. Foams, however, tend to creep.
There therefore remains a need for a durable, silent, and cost effective solution for evenly distributing the forces applied onto a curtain of a roll-up door system. The present invention proposes a solution to such problem. This and other advantages of the invention are described more in detail in the following sections.
The present invention is defined in the appended independent claims. Preferred embodiments are defined in the dependent claims. In particular, the present invention concerns a fast roll-up door for closing an aperture, said roll-up door comprising:
(a) a curtain having two opposite lateral edges extending along a longitudinal direction, and two opposite end edges joining the lateral edges, each of the two lateral edges being held in,
(b) a pair of elongated guiding rails suitable for holding the lateral edges of the curtain, and for guiding them as the curtain is being wound or unwound about a rotating axle, X1,
characterized in that, the curtain comprises at least one resilient portion (3a) extending parallel to said lateral edges, said resilient portion being suitable for reversibly stretching along a transverse direction, normal to the longitudinal direction, from a rest configuration, L1, to a stretched configuration, L1=L1+ΔL, upon application of a pressure, P, applied substantially normal onto the surface of the curtain, and for returning substantially to its rest configuration, L0, upon release of said pressure.
The expression “longitudinal direction” refers herein to the direction defined by the two parallel guiding rails. The expression “transverse direction” refers to a direction normal to the longitudinal direction and comprised within the plane defined by the curtain in its rest configuration. The two end edges of the curtain preferably extend along the transverse direction.
In a preferred embodiment, the at least one resilient portion of the curtain comprises a corrugated portion defined by ridges and valleys extending parallel to the whole length of the lateral edges, wherein two adjacent ridges of the corrugated portions at rest are separated by a rest distance, d0, and such that the distance separating two adjacent ridges of the corrugated portions increases upon application of a pressure, P, applied substantially normal onto the surface of the curtain, and returns substantially to its rest distance, d0, upon release of the force.
Alternatively or concomitantly, the at least one resilient portion can be made of an elastomeric material such as a polyurethane rubber; a silicone rubber; a thermoplastic elastomer (TPE), or other types of known elastomeric materials.
The curtain preferably comprises a central portion flanked by two lateral strips, each having a free edge forming the lateral edges of the curtain. The at least one resilient portion of the curtain is comprised within at least one of said two lateral strips (3), preferably both lateral strips comprise one such resilient portion. The lateral strips are preferably bonded to the central portion of the curtain by welding, gluing, stitching, or combinations thereof. In yet a preferred embodiment, the central portion of the curtain comprises two panes separated by a resilient strip extending along the central portion of the curtain, parallel to the whole length of the lateral edges of the curtain, said resilent strip being suitable for reversibly stretching along a transverse direction, normal to the longitudinal direction, from a rest configuration to a stretched configuration upon application of a pressure, P, applied substantially normal onto the surface of the curtain, and for returning substantially to its rest configuration upon release of said pressure.
The lateral edges of the curtain formed by the free edge of the lateral strips advantageously comprise a continuous bead or a series of discontinuous beads suitable for sliding along the guiding rails and for holding the lateral edges of the curtain in said guiding rails upon application of a force in the transverse direction which is lower than a given pull-out force, Fp0. Above said pull-out force, the bead preferably pulls out of the guiding rails, so as to avoid tearing of the curtain or damages to the guiding rails.
Each resilient portion is preferably suitable for stretching by a length increase, ΔL, in a direction normal to the lateral edge upon application of a force, F, applied onto the curtain, which is comprised within the linear upper and lower boundaries defined by the relationship, F=ki·L, wherein i=1 or 2, and wherein k1=0.4 to 0.6 N/mm and k2=0.7 to 1.0 N/mm.
In a preferred embodiment, the fast roll-up door of the present invention comprises a system for automatic re-insertion of a lateral edge of the curtain into the corresponding guiding rail in case the latter pulled out therefrom, such as if the curtain had been exposed to a force larger than the pull-out force, Fp0.
The present invention also concerns a process for producing a curtain suitable for use in a fast roll-up door as defined above, said process comprising the following steps:
(a) Providing a central portion of a curtain, said central portion being flexible and comprising two parallel lateral edges,
(b) Extruding a lateral strip comprising a resilient portion, and at least one planar coupling portion;
(c) Coupling the planar coupling portion of a lateral strip as defined above to both lateral edges of the central portion of the curtain.
In a preferred embodiment, the extruded strip comprises a lateral strip comprising a free edge provided with a bead, and one planar coupling portion. The extruded strip may also be instead or additionally, a central strip comprising two planar coupling portions flanking on either side the resilient portion.
As discussed above, it is preferred that the resilient portion of the strip comprises a corrugated portion defined by ridges and valleys extending parallel to the whole length of the strip. It is also preferred that coupling a lateral strip to both lateral edges of the central portion of the curtain be carried out by welding, gluing, stitching, or combinations thereof.
Welding is preferred.
For a fuller understanding of the nature of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawings in which:
As shown in
Guiding rails (4) are mounted, parallel to each other, on two opposite sides (30) of the aperture (20) with appropriate fixing means, well known to a person skilled in the art, such as profiles (10) as illustrated in
As illustrated in
As illustrated in
A roll-up door according to the present invention takes profit of the same principle as used in WO9220895 to allow a revesible transverse movement of the curtain upon application of a pressure thereon, but instead of allowing the guiding rails to move transversally, it is a resilient portion (3a) extending parallel to and along the whole length of said lateral edges of the curtain which is suitable for reversibly stretching along the transverse direction from a rest configuration, L0, to a stretched configuration, L1=L0+ΔL, upon application of a pressure, P, applied substantially normal onto the surface of the curtain, and for returning substantially to its rest configuration, L0, upon release of said pressure. As shown in
In a preferred embodiment illustrated in
An additional and quite unexpected advantage of the corrugated portion (3a) is that upon winding the curtain on a drum (2), crests and valleys of the corrugated portions of one rolled layer interlock with the crests and valleys of the adjacent layers on top and below in the drum. This permits to prevent any lateral sliding of the curtain which can happen when repeatedly winding and unwinding a curtain at high speed about a drum (2). This ensures that the curtain is wound straight about the drum and does not slid sideways, thus ensuring a good winding of the curtain without folds and wrinkles that could make bad aesthetical effects and/or curtain wear.
In an alternative configuration illustrated in
It is clear that both embodiments illustrated in
The resilient portion (3a) must be able upon application of a transverse force, F, to the curtain to stretch from a rest configuration, L0, to a stretched configuration, L1, and return to its rest configuration, L0, upon release of the force. The reversibility of the stretch behaviour of the resilient portion (3a) of the curtain can span anything between and including an elastic behaviour as illustrated with a thick solid line in
In a preferred embodiment, the curtain comprises a central portion (1c) flanked by two lateral strips (3), each having a free edge forming the lateral edges of the curtain. The resilient portions (3a) of the curtain are comprised within said two lateral strips (3). The central portion (1c) of the curtain can be made of any material traditionally used for such purpose, such as fabric of polyester or aramid fibres impregnated with a polymer such as PVC, polyurethane, silicone, yielding good mechanical stability and imperviousness to fluids, such as rain, wind, and the like. As illustrated in
a planar coupling portion (3p) for coupling the strip to the central portion (1c) of the curtain;
if it applies, a corrugated portion (3a);
and preferably a bead (3b) continuous or discontinuous, and suitable for engaging in a sliding relationship inside a C-profile forming the guiding rail (4) and for disengaging upon application of a transverse pull-out force, Fpo.
The planar coupling portion (3p) of the lateral strips (3) may be coupled to the central portion (1c) of the curtain by welding, gluing, stitching, or combinations thereof. By this means, the curtain (1) can be produced in a continuous process, which is not restricted by the size of the curtain, and very simple to mount on an aperture (20), by simply solidly fixing the guiding rails (4) to lateral supports (30) flanking either sides of the aperture. No particular calibration of any springs or other features is required for the resilient portion to function as desired.
In yet a preferred embodiment illustrated in
The manufacturing of a curtain (1) for a fast roll-up door according to the present invention is very simple and economical. As illustrated in
(a) Providing a central portion (1c, 1cr, 1cl) of a curtain (1), said central portion (1c) being flexible and comprising two parallel lateral edges (cf.
(b) Extruding (40) a strip (3, 3c) comprising a resilient portion (3a), and at least one planar coupling portion (3p);
(c) Coupling the at least one planar coupling portion (3p) of said extruded strip (3, 3c) to the central portion (1c) of the curtain (cf.
The extruded strip can be a lateral strip (3) comprising a free edge provided with a bead (3b), and one planar coupling portion (3p); The extruded strip can be a central strip (3c) comprising two planar coupling portions (3p) flanking on either side the resilient portion (3a); As shown in
The fast roll-up door of the present invention therefore provides all the advantages of even force distribution along the whole length of both lateral edges of a curtain as described in WO9220895 but at a lower cost, because the curtain can be provided with the resilient portions (3a) discussed above in plant and with a fully automated process.
Installation of a roll-up door according to the present invention is therefore exactly the same as for a state of the art roll-up door devoid of any force distributing system.
Number | Date | Country | Kind |
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1450153-0 | Feb 2014 | SE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2015/052763 | 2/10/2015 | WO | 00 |