EP1600599A1

EP1600599A1 - Safety device for avoiding the fall of roller shutters and gates in case of spring breakage

Info

Publication number: EP1600599A1
Application number: EP04425324A
Authority: EP
Inventors: Mario Gnaccarini; Luigi Gilli
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-05-07
Filing date: 2004-05-07
Publication date: 2005-11-30

Abstract

A safety device (1) is disclosed for avoiding the fall of roller shutters and gates in case of breakage of at least one compensating spring (14) contained in a spring-holder box (12): such device (1) allows lifting and lowering the roller shutter or gate during the intervention of such device (1).

Description

The present invention refers to a safety device for avoiding the fall of roller shutters and gates in case of spring breakage.
As known, roller shutters and gates (hereinbelow briefly called globally "gates") can be enlived with winding systems composed of a fixed or rotating winding shaft; the winding system with fixed winding shaft is equipped with two or more, substantially cylindrical spring-holder boxes that are coaxial to the winding shaft and rotating thereon; function of these spring-holder boxes, to which a roller shutter side is secured, is supporting and allowing to wind and contain a compensating spring of the spiral type; purpose of the spring is counterbalancing, at least partially, the roller shutter weight, returning, during its opening phase, the energy stored as torque during its closing phase, making thereby its handling by an operator easier.
Taking into account the roller shutter weight, that sometimes is extremely high, it is obvious that, for safety reasons (such thing in addition being imposed by law in some Countries, such as for example the European Community through UNI EN 12604 standard), it is necessary to provide the roller shutter or gate winding system with devices that prevent its fall in case of malfunction or breakage of one or more spring-holder boxes, typically due to the yield of the compensating spring contained therein.
Currently, there are on the market different arrangements of the so-called "fall-preventing systems" for roller shutters and gates, such systems however having several inconveniences; some of such systems, in fact, in case of compensating spring breakage, block the roller shutter or gate in the position in which it is upon breaking, making it impossible to further move it unless after an intervention by a trained operator, since the compensating spring is contained within the spring-holder box and is not accessible unless the roller shutter winding system is completely disassembled. It is obvious that such inconvenience is extremely cumbersome, above all if one considers that roller shutters and gates, mostly those that weigh a lot, are above all used to protect accesses and windows of commercial activities, and are moved when closing, a situation in which statistically the compensating springs break more frequently, generally at a late hour: in such situation, having to foresee that the commercial area cannot be adequately protected due to the locked roller shutter, unless a specialised intervention occurs aimed to replace the damages elements, skilled operators being generally found with difficulty during the night, is a source of sure problems and discomforts.
Other arrangements of "fall-preventing systems" allow that, once blocked, it is possible to unlock the safety device in order to take care of closing the roller shutter and gate; these arrangements provide that, once blocked, by slightly pushing the roller shutter upwards, the fall-preventing system is disengaged, allowing the roller shutter to go down; if however the "fall-preventing system" was triggered due to the breakage of many compensating wheels, the disengagement of the safety device can generate the sudden and brusque fall of the roller shutter, creating more than likely physical damages to the roller shutter operator.
Object of the present invention is solving the above prior art problems, by providing a safety device for avoiding the fall of roller shutters and gates in case of spring breakage that, even in case of intervention, allows equally to be able to move the roller shutter under total safety, also in case of breakage of many compensating springs.
The above and other objects and advantages of the invention, as will appear from the following description, are obtained by a safety device for avoiding the fall of roller shutters and gates as disclosed in claim 1. Preferred embodiments and non-trivial variations of the present invention are object of the dependent claims.
The present invention will be better described by some preferred embodiments thereof, provided as a non-limiting example, with reference to the enclosed drawings, in which:

FIG. 1 shows a perspective view of an embodiment of the safety device for avoiding the fall of roller shutters and gates in case of spring breakage according to the present invention;
FIG. 2 shows an exploded view of the device according to the present invention shown in FIG. 1;
FIG. 3 shows a sectional view of the device according to the present invention shown in FIG. 1;
FIG. 4 shows a view of the device according to the present invention with respect to the sectional plane A-A shown in FIG. 3;
FIG. 5 shows a view of the device according to the present invention with respect to the sectional plane B-B shown in FIG. 3;
FIG. 6 shows a view of the device according to he present invention with respect to arrow C shown in FIG. 3;
FIG. 7 shows a view of the device according to the present invention with respect to the sectional plane D-D shown in FIG. 3;
FIG. 8 shows a perspective view of an element of the device according to the present invention shown in FIGS. 1 to 7;
FIG. 9 shows a perspective view of another element of the device according to the present invention shown in FIGS. 1 to 7;
FIG. 10 shows a perspective view of another element of the device according to the present invention shown in FIGS. 1 to 7; and
FIGS. 11 to 18 show a sequence of intervention steps of the device according to the present invention.

With reference to Figures 1 to 10, it is possible to note that the safety device 1 for avoiding the fall of roller shutters and gates in case of spring breakage is composed of a static element, connected to a fixed winding shaft 10, and of a dynamic element, adapted to rotate around the winding shaft 10 in order to allow moving a roller shutter or gate suitably connected thereto.
For a more detailed description of the operation of device 1, it is here useful to previously define a first rotation direction of the dynamic element, defined by the roller shutter winding movement around the winding shaft 10 and shown in the Figures by the curvilinear arrow P, and an opposite movement thereto defining a second rotation direction of the dynamic element shown in the Figures by the curvilinear arrow S.
The dynamic element is preferably composed of:

a spring-holder box 12, adapted to contain a compensating spring 14 and rotating around the winding shaft 10;
a rotating crank pin 16, passing through the side disks of the spring-holder box 12, on whose eccentric central portion, arranged internally to the spring-holder box 12 and interposed between its two side disks, a compensating spring 14 end is secured, and on whose opposite coaxial ends, a first elastic return element 18, and a locking element 20, sliding along its end of the crank pin 16, coupled with an elastic thrust element 22, are respectively arranged. It is moreover useful to provide that the sliding of the blocking element 20 is guided by a guiding element, preferably composed of a first driving pin 24 integral with the crank pin 16 cooperating with an elongated slot 26 of the blocking element 20. The crank pin 16 has further the chance of rotating between a first position (rest position) defined by a first abutment element 28 and a second position (intervention position) defined by a second abutment element 30. In such configuration, the crank pin 16 is subjected to two opposite elastic traction forces, one exerted by the compensating spring 14 and the other by the first elastic return element 18. During the normal roller shutter operation, the compensating spring 14 exerts a greater elastic force than the one of the first elastic return element, consequently keeping the crank pin 16 in its first position; in case of compensating spring 14 breakage, the force exerted by the first elastic return element 18 prevails taking the crank pin 16 in its second position, generating the device 1 intervention with the modes described below. In order to prevent that the broken compensating spring 14 can hinder the suitable crank pin 16 movement, it is possible to position a third and a fourth abutment element of wisecrack 21, 23 between the two side disks which compose the spring-holder box 12 in order to impose to the broken compensation spring 14 a "bridge" shape astride the crank pin 16 avoiding therefore every interference between the crank pin 16 and the broken compensating spring 14. Further, in order to limit the axial movement of the device 1, it is possible to provide for the use of a securing pin 48, for example passing through the winding shaft 10, that abuts against the spring-holder box 12.

The static element of the device 1 according to the present invention is substantially composed of a collar 32, externally integral with the winding shaft 10, on which a blocking cylinder 34 is rotatingly and slidingly keyed-in, such cylinder 34 being equipped, on its end facing the spring-holder box 12 side from which the blocking element 20 projects, with a toothed disk 36 comprising, on its external circumference, a plurality of blocking teeth 38, each tooth 38 equipped with a blocking outline 52 adapted to cooperate with the blocking element 20 when this latter one is in its intervention position and the dynamic element of the device 1 rotates according to direction S. The static element is also composed of a sliding outline 54 adapted to allow the blocking element 20 to slide when the dynamic element of the device 1 rotates according to direction P, as can be seen afterwards in greater detail.
The blocking cylinder 34 is further equipped with at least one suitably curvilinear slot 40 that, cooperating with at least one second guiding pin 42 integral with the winding shaft 10, constrains the rotation-translation movement of the blocking cylinder 34 with respect to collar 32. The blocking cylinder 34 is further equipped with at least one second elastic return element 44 whose function will appear evident from the following description. On the external surface of the spring-holder box 12 facing towards the static element, an unlocking pin 46 is further secured, adapted to cooperate with the sliding outline 54 of the tooth 38 of the toothed disk 36 according to the following modes.
The blocking element 20 is further equipped with a third abutment element 50 adapted to cooperate with the tooth 38 with the modes that will be described below.
It is further possible to arrange a sensor (not shown) that signals the device 1 intervention according to the present invention.
With reference now to Figures 11 to 18, an example of a sequence of intervention steps of the device 1 according to the present invention will now be described.
FIG. 11 shows a normal roller shutter operating step; as can be seen, the static element and the dynamic element of the device 1 do not mutually interfere (in particular, the blocking element 20 is kept in its first position, against the first abutment element 28, by the unbroken compensating spring 14 traction as previously described; in such position, the blocking element 20, as well as the unlocking pin 46, is at such a distance from the teeth 38 of the toothed disk 36 that it does not come in contact with the teeth). Moreover, the blocking cylinder 34 is kept by the second elastic return element 44 in a rest position, position in which the toothed disk 36 and the teeth 38 are adequately separated from the blocking element 20 and the unlocking pin 46 in order not to get in contact with these latter ones during the device 1 dynamic element rotation during normal roller shutter operation, in which the second guiding pin 42 is in a first rest position at one end of the slot 40. In this way, the dynamic element can rotate along both directions P and S without obstructions by the static element.
FIG. 12 shows the step in which the compensating spring 14 breaks; in such step, the blocking element 20, not subjected any more to the elastic force of the compensating spring 14, rotates in its initial intervention position against the second abutment element 30 under the thrust of the first elastic element 18 and comes to interfere with the maximum circumference of the toothed wheel 36 defined by external portions of the teeth 38. From FIG. 13 it is possible to note that the roller shutter fall brings the spring-holder box 12 to rotate along rotation direction S, and the blocking element 20, engaging the blocking outline 52 of a tooth 38, makes the blocking cylinder 34 rotate concurrently therewith; this latter one, due to the coupling between slot 40 and second guiding pin 42, performs a rotary and translating movement for approaching the dynamic element, consequently generating the traction of the second elastic return element 44; such translating movement, due to the tooth 38 abuttingly engaged onto the third abutment element 50, simultaneously brings about the thrust of the blocking element 20 that slides along its own end of the crank pin 16, loading the elastic thrust element 22, till a final intervention position; the rotary motion of the blocking cylinder 34 ends when the second driving pin 42 reaches a second position at the end of the slot 40 opposite to the rest position one, taking the blocking cylinder 34 in its blocking position, such thing, due to the coupling with blocking element 20 and engaged tooth 38 of the toothed wheel 36, generates the following blocking of the dynamic element of the device 1, and consequently stops the roller shutter fall.
FIG. 14 shows a step in which, by slightly lifting the roller shutter or gate, and then by rotating the dynamic element of the device 1 by a few degrees according to the rotation direction P, the blocking element 20 disengages itself from the blocking outline 52 of the tooth 38 and, under the thrust of the elastic thrust element 22, goes back to its initial intervention position, while the blocking cylinder 36, due to the outline of the slot 40 that cooperates with the second driving pin 42 and keeps it in its second position, remains in its blocking position.
FIG. 15 shows that, going on rotating the roller shutter or gate, and then rotating the dynamic element according to direction P, the unlocking pin 46 gets in contact with the sliding surface 54 of a tooth 38.
As shown in FIG. 16, going on lifting the roller shutter or gate, the unlocking pin 46 rotates the blocking cylinder 34 according to direction P; in such situation, due to the cooperation between slot 40 and guiding pin 42 and the action of the second elastic return element 44, the blocking cylinder 34 performs a rotary movement along direction P and a translating movement going away from the dynamic element of the device 1 until, as shown in FIG. 17, the side surface of the toothed disk 36 comes to abut against the internal surface of the blocking element 20. At that time, as shown in FIG. 18, by again rotating the dynamic element according to direction S, the device 1 goes back in the situation shown in FIG. 12, but engaging a following tooth 38 according to direction S, thereby allowing the roller shutter or gate to be lowered by a length thereof depending on the angular distance between two following teeth 38. It is evident that, by sequentially performing the above-described steps many times, using the device 1 according to the present invention, it is always possible to completely lower the roller shutter or gate in total safety, even in case of breakage of many compensating springs 14.
It is further possible, by adopting the device 1, to be able to provide, even in case of breakage of one or more compensating springs 14, for the complete roller shutter winding since, starting from the situation shown in FIG. 17, going on lifting the roller shutter or gate, and then rotating the dynamic element according to direction P, the blocking element 20 slides in succession on the sliding outline 54 of all teeth 38 that it meets without obstructions. Also in this case the roller shutter handling is performed under complete safety, since at any time it is decided not to lift the roller shutter or gate any more, the device 1 will take care of blocking its descent with the previously-described modes.

Claims

Safety device (1) for avoiding a fall of roller shutters and gates in case of breakage of at least one compensating spring (14) contained in a spring-holder box (12), characterised in that it allows lifting and lowering said roller shutters and gates during an intervention of said device (1).
Safety device (1) according to claim 1, characterised in that it comprises a dynamic element and a static element, said dynamic element being composed of:

said spring-holder box (12), adapted to contain said compensating spring (14) and to rotate around a fixed winding shaft (10);

a rotating crank pin (16), passing through said spring-holder box (12), having a central eccentric portion on which an end of said compensating spring (14) is secured, and having two opposite coaxial ends on which, respectively, a first elastic return element (18), and a blocking element (20) are arranged, said blocking element (20) sliding along said own end of said crank pin (16), coupled with at least one elastic thrust element (22), said crank pin (16) being adapted to rotate between a first position defined by a first abutment element (28) and an intervention position defined by a second abutment element (30); said static element being connected to said fixed winding shaft (10) and being composed of a collar (32), externally integral with said winding shaft (10), on which a blocking cylinder (34) is rotatingly and slidingly keyed-in, said blocking cylinder (34) being equipped with a toothed disk (36) comprising, on its external circumference, a plurality of blocking teeth (38) adapted to cooperate with said blocking element (20); said blocking cylinder (34) being equipped with at least one second elastic return element (44) and at least one curvilinear slot (40) cooperating with at least one second guiding pin (42) integral with said winding shaft (10), adapted to control and constrain a rotating and translating movement of said blocking cylinder (34) with respect to said collar (32); said spring-holder box (12) being further equipped with an unlocking pin (46) adapted to cooperate with at least one tooth (38) of said toothed disk (36); and said blocking element (20) being equipped with a third abutment element (50) adapted to cooperate with at least one of said teeth (38).
Safety device (1) according to claim 1 or 2, characterised in that each one of said teeth (38) is equipped with a blocking outline (52) adapted to cooperate with said blocking element (20) and with a sliding outline (54) adapted to cooperate with said blocking element (20) and with said unlocking pin (46).
Safety device (1) according to claim 1 or 2, characterised in that said sliding of said blocking element (20) is guided by a guiding element.
Safety device (1) according to claim 4, characterised in that said guiding element is composed of a first guiding pin (24) integral with said crank pin (16) cooperating with a slot (26) of said blocking element (20).
Safety device (1) according to any one of the previous claims, characterised in that it is equipped with at least one securing pin (48) integral with said winding shaft (10) adapted to limit an axial movement of said dynamic element.
Safety device (1) according to any one of the previous claims, characterised in that it comprises a sensor adapted to indicate an intervention of said safety device (1).
Safety device (1) according to any one of the previous claims, characterised in that it comprises a third and a fourth abutment element (21, 23) provided between side disks component said spring-holder box (12) act to prevent any interference between said crank pin (16) and said broken compensating spring (14).
Process for triggering a safety device (1) according to any one of the previous claims, a rotation direction (P) of said dynamic element being determined by a winding direction of said roller shutter or gate around said winding shaft (10) and a rotation direction (S) of said dynamic element being opposed to said rotation direction (P), characterised in that it comprises the steps of:

in the event that said compensating spring (14) breaks, rotating said blocking element (20) along said defined initial intervention position from said abutment element (30) through an action of said first elastic element (18);

rotating, along said rotation direction (S), said dynamic element under an action of a fall or said roller shutter and gate;

engaging said blocking outline (52) of a tooth (38) with said blocking element (20);

rotating said blocking cylinder (34) along said rotating direction (S) through an action of said rotation of said dynamic element; said blocking cylinder, due to a coupling between said slot (40) and said second guiding pin (42) performing a rotating and translating movement for approaching said dynamic element and generating a traction of said second elastic return element (44);

thrusting said blocking element (20) and loading said elastic thrust element (22) till a final intervention position through said tooth (38) abuttingly engaging said third abutment element (50);

ending said rotating movement of said blocking cylinder (34) through said second guiding pin (42) reaching an end position of said slot (40);

blocking said rotation of said dynamic element through a coupling between said blocking element (20) and said tooth (38) of said toothed wheel (36).
Process for lowering a roller shutter or gate when a device (1) according to any one of Claims 1 to 7 has triggered, characterised in that it comprises the steps of:

lifting said roller shutter or gate and rotating said dynamic element according to said rotation direction (P);

disengaging said blocking element (20) from said blocking outline (52) of said tooth (38);

taking back said blocking element (20) in said initial intervention position through an action of said elastic thrust element (22);

getting in contact said unlocking pin (46) with said sliding surface (54) of a tooth (38);

rotating according to said rotation direction (P) and moving away from said dynamic element said blocking cylinder (34) through an action of said second elastic return element (44) and a cooperation between said slot (40) and said guiding pin (42);

abutting a side surface of said toothed disk (36) to an internal surface of said blocking element (20);

rotating said dynamic element along said direction (S) and engaging a following tooth (38) of a previous tooth along said direction (S) with said blocking element (20); and

repeating the previous steps in order to lower the roller shutter or gate at will.
Process for lifting a roller shutter or gate when a device (1) according to any one of Claims 1 to 7 has triggered, characterised in that it comprises the steps of:

lifting said roller shutter or gate and rotating said dynamic element according to said rotation direction (P);

disengaging said blocking element (20) from said blocking outline (52) of said tooth (38);

taking back said blocking element (20) in said initial intervention position through an action of said elastic thrust element (22);

rotating along said rotation direction (P) and moving away from said dynamic element said blocking cylinder (34) through an action of said second elastic return element (44) and a cooperation between said slot (40) and said guiding pin (42);

sliding said blocking element (20) onto said sliding surface (54) of a tooth (38) following said engaged tooth (38) along said direction (P); and

repeating the previous steps in order to lift the roller shutter or gate at will.