EP0894936A1 - Fall protection device for vertically retractable closures with a shutter mounted on a fixed tube - Google Patents

Abstract

The anti-drop mechanism for a roller shutter door mounted on a horizontal shaft (1) comprises a fixed flange on the shaft and an adjacent rotary flange fixed to the shutter so that it rotates relative to the fixed flange as the shutter moves. The rotary flange has a number of centrifugal locking elements (25,26,27) in the form of spring-loaded and pivoted levers with end claws (25a) which engage with apertures (16,17) in a rim (12) on the fixed flange surrounding the levers when the normal operating speed of the shutter is exceeded.

Description

The invention relates to a safety device for closing vertical erasure provided with an apron mounted around a fixed tube, said device for safety being intended to prevent the apron from falling in the event of an element failure of the carrier system of said curtain.

For obvious security reasons, it is common to provide vertical-closing closing curtains for retaining devices intended to avoid the apron falling in the event of a failure of a system element carrier. In fact, in certain countries, the standards in force require equipping such curtains of a safety device.

Regarding curtains with springs of compensation of the deck mounted around a fixed tube, these springs are the elements most likely to fail, and the most common solution current is to design compensating springs incorporating their own safety system in case of breakage. However, this solution presents mainly two drawbacks. Indeed, and in the first place, it leads to a increase in the cost price of the curtains due to the multiplication of the number safety devices equivalent to the number of springs, and moreover it requires replace the spring fitted with its safety device when this breaks latest. In addition, when a compensating spring breaks, the bulkhead is blocked in the position it is in during this break. The springs of compensation are housed inside the apron winding and are not therefore directly accessible only if this deck is fully lowered. In these conditions, the change of the broken compensating spring proves practically systematically a hazardous operation frequently requiring deterioration the apron for access to said spring.

Regarding the closing curtains mounted around of a rotating tube, there are currently a plurality of security systems designed according to the same principle and generally comprising a shaped part disc, or rotor, adapted to be secured to the rotary tube so as to be driven in rotation with the latter, at least one stop piece pivotally mounted on the rotor around an axis parallel to the axis of the rotary tube, and a fixed part, or stator, of shape general annular, arranged around the rotor and provided with an internal peripheral face having housings for blocking the free end of the stop piece.

The principle of all these safety devices is to use the centrifugal force exerted on each pivoting stop piece, to bring this last in an apron locking position when this centrifugal force becomes too large, corresponding to an abnormal excessive speed of unfolding of the curtain.

In practice, such safety devices give full satisfaction when intended to equip weight closing curtains relatively weak such as for example used for constructions for use residential. However, they turn out to have drawbacks when the curtains , for example as used for industrial buildings, have relatively large dimensions and therefore weights.

Indeed, by design, these safety devices have stop pieces which are subject to kickback when the curtain rotates, which should be controlled if we want to guarantee their effectiveness.

However, in practice, the control of this rebound phenomenon proves to be a difficult problem to solve, such as emerges for example from the examination of the conventional type safety device described in US Patent 5,494,093, the peripheral face of the stator has inclined grooves towards which the end of the abutment piece is guided by ramps formed on said peripheral face.

According to this conception, the rebound phenomenon is avoided thanks to to the combined shape of the end of the stop piece and the grooves which allows to obtain a jamming effect of said abutment piece inside one of said gorges.

However, the wedging force being proportional to the weight aprons, the use of such a safety device with heavy aprons relatively high leads either to a blockage with a significant wedging effect of the abutment piece inside a groove, or to a non-elastic deformation of the stator.

In the first hypothesis, it is practically impossible to loosen the stopper piece without accessing the safety device directly, and this operation requires the disassembly of the drive means of the rotary shaft in order to access this safety device, then the disassembly of said safety device security which can be delicate since the latter is blocked. In addition, during this disassembly, it is frequent that the device is damaged, which imposes its replacement.

In the second hypothesis, the stator is deformed by residual way and the subsequent operation of the safety device is no longer guaranteed, so the latter must also be replaced in this case.

Another solution, described in patent DE 24 33544, and also applicable to curtains with a rotating tube, consists in driving in rotation with the tube of the flyweights capable of pivoting about axes parallel to the axis of said axis tube, so that one of said weights comes to engage in teeth of stop of a fixed flange when the centrifugal force acting on it exceeds a given value determined by elastic means, in a position where it is held automatically by a ratchet.

According to this device, the rebound phenomenon is therefore controlled by means of a ratchet which maintains the flyweight in its position blocking. However, this solution leads to the same drawback as that mentioned above. aprons with compensating springs, i.e. the apron is blocked in the position it is in when a motor element breaks.

The present invention aims to overcome this drawback and has for essential objective of providing a locking safety device with a deck mounted around a fixed tube, allowing the deck to descend completely once said device is activated.

Another object of the invention is to provide a device for safety causing no wear during normal operation of the curtain.

• un flasque fixe solidarisé autour du tube fixe et présentant, au moins partiellement, un rebord périphérique doté d'au moins une ouverture radiale, dite de blocage, axée dans un plan vertical A,
• un flasque mobile disposé autour du tube fixe en regard du flasque fixe, et solidarisé au tablier de façon à être entraíné en rotation avec ce dernier,
• au moins un élément de blocage articulé, vers une de ses extrémités, sur le flasque mobile autour d'un axe parallèle à l'axe du tube fixe, chacun desdits éléments de blocage étant agencé de façon à se trouver axé dans le plan vertical A et comportant une extrémité libre en forme de griffe de forme adaptée pour pénétrer dans chaque ouverture radiale du flasque fixe, et se bloquer dans ladite ouverture dans une position où au moins une portion de ladite extrémité en forme de griffe se trouve dans le prolongement de cette ouverture radialement à l'extérieur du rebord périphérique délimitant cette dernière,
• et associés à chaque élément de blocage, des moyens élastiques aptes :
  • à maintenir l'élément de blocage dans une position de fonctionnement normal où son extrémité libre se déplace selon une circonférence centrée sur l'axe du tube fixe de rayon inférieur à la distance radiale entre ledit axe et chaque ouverture radiale, en deçà d'une force centrifuge prédéterminée sollicitant ledit élément de blocage,
  • à autoriser un pivotement de l'élément de blocage de façon à conduire son extrémité libre à venir se bloquer dans une ouverture radiale lorsque la force centrifuge excède la valeur seuil prédéterminée.

To this end, the invention relates to a security device comprising:

• a fixed flange secured around the fixed tube and having, at least partially, a peripheral rim provided with at least one radial opening, called a blocking opening, centered in a vertical plane A,
• a movable flange disposed around the fixed tube opposite the fixed flange, and secured to the apron so as to be rotated with the latter,
• at least one blocking element articulated, towards one of its ends, on the flange movable about an axis parallel to the axis of the fixed tube, each of said blocking elements being arranged so as to be centered in the vertical plane A and comprising a free end in the shape of a claw adapted to penetrate into each radial opening of the fixed flange, and to lock in said opening in a position where at least a portion of said end in the shape of a claw is in the extension of this opening radially outside the peripheral rim defining the latter,
• and associated with each blocking element, suitable elastic means:
  • maintaining the locking element in a normal operating position where its free end moves along a circumference centered on the axis of the fixed tube with a radius less than the radial distance between said axis and each radial opening, within a predetermined centrifugal force acting on said blocking element,
  • authorizing a pivoting of the blocking element so as to cause its free end to come to block in a radial opening when the centrifugal force exceeds the predetermined threshold value.

The principle according to the invention therefore also consists in using the centrifugal force exerted on a blocking member associated with means elastic to bring the latter into a locking position of the apron when the centrifugal force becomes too great, corresponding to excessive speed representative of the failure of a driving element.

However, the design of this safety device including each blocking element rotates with the apron around the fixed tube, and one of which said blocking elements is housed in a radial opening of a flange fixed integral with said fixed tube with its end in the shape of a claw extending in the extension of this opening, in the event of a motor element breaking, allows to control the rebound phenomenon without leading to any deterioration of said security device. Indeed, the rebound of the blocking element cannot intervene because the peripheral rim delimiting the opening in which penetrates said blocking element is located radially inside the end in claw shape of the latter and therefore acts as a radial stop preventing its pivot to its normal operating position. So, in the first place, such safety device proves to be of excellent reliability. In addition, it authorizes, once the assured blocking, and by raising the said apron somewhat, to bring the element blocking in its initial position and so being able to then descend completely this apron by supporting it during this descent. The driving force broken is thus thus directly accessible and it can then be proceeded easily at its change. Note, moreover, that it can then also be proceeded easily to a possible verification of the state of the safety device.

In addition, under normal operating conditions of the curtain, such a safety device has no rotating element in contact with a fixed element so that there are no wearing parts.

Finally, this safety device does not have to be replaced and can be reused as it is after the rupture of a driving element.

According to another characteristic of the invention, each radial opening of the fixed flange is formed on a peripheral portion of said flange arranged to be along the portion of upward path of the axis articulation of each locking member, according to the direction of descent of the deck.

This arrangement of each radial opening leads, in fact, each locking element to be pivoted not only under the effect of an increase centrifugal force but under the effect of this force plus its own weight said blocking element. Therefore, this safety device has a time of very fast reaction, and can also be calibrated very precisely by means of an adequate calibration of the elastic means.

According to another characteristic of the invention, the fixed flange consists of a disc with spaced return elements on its periphery perpendicular to said disc, delimiting slots forming the openings of blocking.

This design makes it possible, in fact, to produce, by welding inserts or by folding using unsophisticated techniques, returns with a substantial thickness capable of avoiding any risk of deformation of these when the safety device is activated.

In addition, preferably, the security device includes two returns arranged substantially over a quarter of the circumference of the disc extending from the lower generator thereof. The presence of two successive radial blocking openings thus constitute double security locking the apron.

According to another characteristic of the invention, the flange mobile consists of a disc with a diameter significantly larger than that of the disc of the fixed flange, provided with a peripheral rim arranged to cover radially the blocking openings of said fixed flange.

Always for security purposes, and in order to further reduce the maximum travel of the bulkhead, once a driving element is broken, the security preferably comprises at least two blocking elements, the articulation axes are distributed symmetrically with respect to the axis of the fixed tube.

Advantageously, these blocking elements are in number of three arranged so that their axes of articulation form the vertices of a equilateral triangle centered on the axis of the fixed tube.

According to another characteristic of the invention, the means elastic associated with each blocking element consist of a spring arranged to tend to rotate said blocking member towards the axis of the fixed tube. Of more, the movable flange then has, for each locking element, an element limit stop for pivoting of said blocking element under the action of spring.

According to another characteristic of the invention, each element blocking device is provided, near its claw-shaped end, with a transverse notch capable of covering the peripheral edge portion of the flange fixed delimiting an opening after pivoting of said blocking element.

Such a notch, by covering the peripheral rim of the fixed flange, forms a radial stop limiting the pivoting of the elements blocking.

In addition, according to a preferred embodiment, the notch of each blocking element has a rear wall inclined towards the rear, in considering the direction of rotation of said locking element, the peripheral rim of the fixed flange having at each opening a bevelled edge inclination combined with that of said bottom wall.

• la figure 1 une vue en perspective schématique d'un rideau de fermeture à effacement vertical équipé d'un dispositif de sécurité conforme à l'invention,
• la figure 2 est une coupe transversale par un plan vertical A du dispositif de sécurité conforme à l'invention, dans la position non sollicitée de ce dispositif correspondant à un fonctionnement normal du rideau,
• la figure 3 est une coupe longitudinale par un plan B de ce dispositif de sécurité dans sa position non sollicitée,
• la figure 4 est une coupe transversale par le plan A de ce dispositif de sécurité dans sa position sollicitée de blocage du rideau,
• et la figure 5 est une vue en perspective du flasque fixe de ce dispositif de sécurité.

Other characteristics, objects and advantages of the invention will emerge from the detailed description which follows with reference to the appended drawings which represent, by way of non-limiting example, a preferred embodiment. On these drawings which form an integral part of this description:

• FIG. 1 is a diagrammatic perspective view of a closing curtain with vertical erasure equipped with a safety device according to the invention,
• FIG. 2 is a cross section through a vertical plane A of the safety device according to the invention, in the unsolicited position of this device corresponding to normal operation of the curtain,
• FIG. 3 is a longitudinal section through a plane B of this safety device in its unsolicited position,
• FIG. 4 is a cross-section through plane A of this safety device in its requested position for blocking the curtain,
• and Figure 5 is a perspective view of the fixed flange of this safety device.

• un tube fixe horizontal 1 s'étendant entre deux plaques latérales 2, 3,
• des ressorts de compensation tels que 4 logés chacun à l'intérieur d'une bobine telle que 5 et solidarisés à ladite bobine et au tube fixe 1,
• quatre plats bombés tels que 6, 7 de liaison des bobines 5, soudés sur ces dernières, et sur lesquels est solidarisée l'extrémité supérieure du tablier 8.

The safety device according to the invention shown in FIGS. 2 to 4, is intended to equip a vertical blanking closing curtain shown diagrammatically in FIG. 1, and conventionally comprising:

• a horizontal fixed tube 1 extending between two side plates 2, 3,
• compensation springs such as 4 each housed inside a coil such as 5 and secured to said coil and to the fixed tube 1,
• four curved plates such as 6, 7 for connecting the coils 5, welded to the latter, and on which the upper end of the deck 8 is secured.

This safety device firstly comprises a flange fixed 9 having the shape of a disc 10 pierced with a central hole of diameter substantially greater than that of the fixed tube 1, and welded, around the periphery of this orifice, on a sheath 11 of internal diameter conjugated with the external diameter of said fixed tube, said sheath being pierced with diametrically opposite radial orifices making it possible to secure to the fixed tube 1 by means of a screw / nut assembly 1 la. This fixed flange 9 further comprises a peripheral rim 12, presenting substantially over a quarter of the circumference of said flange, a portion 13 of lesser height. This fixed flange 9 also comprises two peripheral notches (masked in the figures) in with regard to which the peripheral rim portion 13 is interrupted, said notches being respectively provided at one of the end zones and in the central zone of this peripheral rim portion 13.

This fixed flange 9 finally comprises two stop parts 14, 15 L-shaped, one of the branches of which is welded to the external face of said flange fixed, and the other branch 14a, 15a of which is housed in a notch, so as to form a stop height greater than that of the peripheral rim 12, delimiting with the latter respectively two radial openings 16, 17. In addition, the face lateral of this branch 14a, 15a, of abutment of the locking elements, has a obviously 18 of triangular section, arranged so as to be on the trajectory of said blocking elements.

In addition, as shown in Figures 2 and 4, the fixed flange 9 is arranged so that the peripheral rim portion 13 extends, starting from the lower generator of disc 10, in the left portion of the dial of said disc, if we consider the direction of descent of the deck 8 materialized by the arrow F.

The safety device also includes a second movable flange 19 arranged to be welded or fixed by means of bolts on the face internal curved plates 6, 7 connecting the coils 5, so as to be driven in rotation with the latter and the deck 8, and arranged opposite the fixed flange 9 of so as to form a housing with the latter.

This movable flange 19 also has the shape of a disc. 20 pierced with a central orifice allowing it to be mounted around the fixed tube 1. In addition, a cage of ball bearings 22 is interposed between the fixed tube 1 and the disc 20, and held on the latter by means of a plate 21 forming an external cage.

This flange 19 also has a peripheral rim cylindrical 23 obtained by folding arranged to radially cover the rim peripheral 12 of the fixed flange 9, and to be secured to the curved plates 6, 7.

This mobile flange 19 is also equipped with three knives blocking 25, 26, 27 rectilinear with a thinned front end in the form of claw such as 25a. Each of these knives 25-27 also has a transverse notch 40 delimiting its claw-shaped end portion 25a and adapted to cover the branch 14a, 15a of the abutment pieces 14, 15 during blocking of the device. This notch 40 also has a bottom wall 40a inclined conjugate of the recess 18 of the abutment pieces 14, 15.

These knives 25-27 are mounted on the disc 20, in line with their rear end by means of articulation axes consisting of each of said knives, and as shown in FIG. 3, in a screw 28 / nut 29 system and in three washers 30, 31, 41 interposed on either side of said disc and said knives.

As shown in the figures, the axes of articulation of the knives 25-27 are evenly distributed on the disc 20 and form the vertices an equilateral triangle centered on the axis of said disc, so that said knives extend along cords of the latter, their claw 25a being at a short distance radial, of the order of two millimeters, from the peripheral edge 12 of the fixed flange 9.

• un ressort à spirale 32 s'étendant orthogonalement par rapport audit couteau et dont les crochets d'extrémité sont engagés respectivement dans un oeillet 33 solidaire du disque 20 et dans une lumière 34 ménagée dans chaque couteau 25-27 à faible distance de la griffe 25a,
• une butée 35, obtenue par découpe et pliage de petites portions de surface du disque 20, et ménagée de façon à être disposée à l'arrière de la griffe 25a de chaque couteau 25-27.

In order to maintain the knives 25-27 in this angular position, each of these is also associated with:

• a spiral spring 32 extending orthogonally to said knife and the end hooks of which are engaged respectively in an eyelet 33 secured to the disc 20 and in a slot 34 formed in each knife 25-27 at a short distance from the claw 25a ,
• a stop 35, obtained by cutting and folding small portions of the surface of the disc 20, and arranged so as to be disposed at the rear of the claw 25a of each knife 25-27.

As shown in Figure 2, in normal operation of the curtain, that is to say for normal speeds of unwinding of the deck 8, in the direction of arrow F, the knives 25-27 are kept in contact against the stops 35 under the action of the springs 32. It should be noted, moreover, that in these operating conditions, no rotating element is in contact with a any fixed element so that there is no risk of wear.

However, in the event of an incident and an increase in the speed of unwinding beyond a predetermined value which can be easily calculated by adjustment of the setting of the springs 32, the knives 25-27 pivot about their axis of articulation, and one of said knives, in the example knife 25, comes first place slide on the portion of the peripheral rim 13, in the radial opening 16, then abut against the stop piece 14, the second stop piece 15 being only designed to increase security.

During this contact between the knife 25 and the stop piece 14, the notch 40 covers the branch 14a of this abutment piece at the recess 18 so that the bottom wall 40a of this notch 40 collects the first stop shock. The second stop shock is received by the wall adjacent transverse of this notch 40 which is pressed radially against the abutment piece 14 and thereby limits the pivoting of the knife 25. Finally, and essentially, any risk of kickback is negated because the shaped end knife claw 25a slides radially outside of the stop piece 14.

Another safety criterion guaranteeing the blocking of the apron 8 resides in the fact that the abutment pieces 14, 15 are arranged along the portion upward path of the knuckle axes 25-27, if we consider the direction of flow F. As a result, the weight of the knives 25-27 adds up centrifugal force and therefore promotes the pivoting of the latter.

Finally, one of the primary advantages of the safety according to the invention resides in the fact that, once the apron 8 is blocked, such as shown in Figure 4, the knife 25 can be unlocked very simply by lifting somewhat said apron, and the latter can then be lowered completely from manually, allowing direct access to the winding system (springs compensators 4 ...).

Claims (10)

Safety device for vertical erasure closure provided with an apron (8) mounted around a fixed tube (1), said safety device being intended to prevent the apron (8) from falling in the event of an element failure of the carrier system and being characterized in that it comprises in combination: a fixed flange (9) secured around the fixed tube (1) and having, at least partially, a peripheral rim (12-15) provided with at least one radial opening (16-17), called a blocking, centered in a vertical plane (A), a movable flange (19) disposed around the fixed tube (1) opposite the fixed flange (9), and secured to the apron (8) so as to be rotated with the latter, at least one blocking element (25-27) articulated, towards one of its ends, on the movable flange (19) about an axis parallel to the axis of the fixed tube (1), each of said blocking elements being arranged so as to be centered in the vertical (A) and comprising a free end (25a) in the form of a claw of shape adapted to penetrate into each radial opening (16-17) of the fixed flange (9) and to lock in said opening in a position where at least a portion of said claw-shaped end is in the extension of this opening radially outside the peripheral rim (12-15) delimiting the latter, and associated with each blocking element (25-27), elastic means (32) suitable: maintaining the locking element (25-27) in a normal operating position where its free end (25a) moves along a circumference centered on the axis of the fixed tube (1) of radius less than the radial distance between said axis and each radial opening (16-17), below a predetermined centrifugal force urging said blocking element, authorizing a pivoting of the locking element (25-27) so as to cause its free end (25a) to come and block in a radial opening (16-17) when the centrifugal force exceeds the predetermined threshold value. Safety device according to claim 1, characterized in that each radial opening (16-17) of the fixed flange (9) is formed on a peripheral portion of said flange arranged to be along the portion of upward path of the articulation axis of each locking member (25-27), depending on the direction of descent of the bulkhead (8). Safety device according to one of claims 1 or 2,
characterized in that the fixed flange (9) consists of a disc (10) having on its periphery spaced return elements (14-15) perpendicular to said disc, delimiting slots (16-17) forming the blocking openings . Safety device according to claims 2 and 3 taken set, characterized in that it comprises two returns (14-15) arranged substantially over a quarter of the circumference of the disc (10) extending from the lower generator of the latter. Safety device according to one of claims 3 or 4,
characterized in that the movable flange (19) consists of a disc (20) of diameter substantially greater than that of the disc (10) of the fixed flange (9), provided with a peripheral rim (23) arranged to cover radially the blocking openings (16-17) of said fixed flange. Safety device according to one of the claims previous, characterized in that it comprises at least two blocking elements (25-27) whose axes of articulation are distributed symmetrically with respect to the axis fixed tube (1). Safety device according to claim 6, characterized in that it comprises three blocking elements (25-27) including the articulation axes form the vertices of an equilateral triangle centered on the axis of the fixed tube (1). Safety device according to one of the claims above, characterized in that each blocking element (25-27) is provided, at proximity of its claw-shaped end (25a) to a transverse notch (40) able to cover the peripheral edge portion (12-15) of the fixed flange (9) defining an opening (16, 17) after pivoting of said blocking element. Safety device according to claim 8, characterized in that the notch (40) of each blocking element (25-27) has a wall bottom (40a) inclined backwards, considering the direction of rotation of said element blocking, the peripheral edge (12-15) of the fixed flange (9) having at the level of each opening (16-17), a bevelled edge (18) of conjugate inclination of that of said bottom wall. Safety device according to one of claims 8 or 9, characterized in that: the elastic means associated with each blocking element (25-27) consist of a spring (32) arranged to tend to pivot said blocking element towards the axis of the fixed tube (1), the movable flange (19) has, for each locking element (25-27), a stop element (35) for limiting the pivoting of said locking element under the action of the spring (32).

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