FR2757775A1 - Ventilation duct shutter to prevent spread of flames and smoke in event of fire - Google Patents

Abstract

The shutter consists of a plate (4) which pivots inside the duct (1) and is turned by a drive shaft (14) between rest and safety positions. The drive shaft has a pre-tensioned spring (19) and is connected to a locking pin (22) which interacts with a rocker (25) which pivots at right angles to the drive shaft. The rocker has a catch which holds the pin in a locked position and is actuated by an electromagnetic control unit to release it.

Description

Firestop device for ventilation duct
The invention relates to a fire protection device for ventilation ducts.

The device of the invention is of the type comprising a blade connected to a drive axis to pivot in the conduit between a standby position and a safety position, a spring member coupled to the drive axis of the blade and capable of being prestressed, locking means capable of assuming a locked state in which the blade is in the standby position with the prestressed spring member and an unlocked state in which the blade is biased in the safety position under the action of the spring member, and control means capable of acting on the locking means to bring them to the unlocked state.

Devices of this type are already known in which the blade is a fire damper mounted inside an air duct passing through a wall or a floor of a building.

This valve is in a normally open waiting position and can be brought into a normally closed safety position, by means of control means to restore the fire resistance characteristics of the wall or the floor.

The blade can also be produced in the form of a smoke extraction flap which is closed in the waiting position and open in the safety position.

The control means suitable for unlocking the blade (flap or flap) to bring it from its standby position to its safety position are usually either self-controlled means operating by temperature detection, or remote-controlled means operating on external order. .

The design of these fire protection devices poses numerous implementation problems.

These devices are generally hidden in false ceilings or walls, which makes them difficult to access and requires disassembly to allow them to be checked at regular intervals, as required by regulations.

Furthermore, it is necessary that these devices operate in a particularly reliable manner in order to be able to pass from their standby position to their safety position in the event of an incident, in particular a fire.

Another problem posed by fire protection devices of the aforementioned type is that, after an incident, it is necessary to be able to return the blade from its safety position to its standby position, while at the same time exerting a prestress on the member. spring.

Since such a fire protection device is generally concealed, it is desirable to be able to carry out this operation, also called "rearming operation", using a motor to carry out remote resetting.

The invention provides a solution to the above problems.

It aims in particular to provide an easily accessible and reliable fire protection device which can be produced in different versions, from a basic version to more advanced versions, starting from the same basic components. .

To this end, the invention provides a fire protection device of the type defined in the introduction, in which the locking means comprise a locking finger connected perpendicularly to the drive axis of the blade, a locking rocker mounted directly to pivot. relative to a housing external to the duct, around an axis orthogonal to the blade drive axis, and comprising a notch capable of retaining the locking finger in the locked state and an actuating tongue projecting beyond outside the housing, and elastic return means suitable for returning the rocker to a rest position in which the locking finger cooperates with the notch of the locking rocker, and in which the control means are arranged to act on the locking lever against the elastic return means for releasing the finger from the notch of the locking lever.

The device of the invention thus comprises simple and robust mechanical means making it possible to maintain the blade (valve or flap) in its standby position, to move it towards its safety position under the action of the control means, and to return it to its standby position to reset the device.

In a simplified embodiment of the invention, the control means comprise self-controlled means comprising a thermal fuse housed in the conduit and coupled to a spring plunger capable of being released and of lifting the locking lever when the thermal fuse reaches a given temperature, the thermal fuse being removable and accessible from the outside of the duct.

In a more advanced embodiment, the control means comprise remote-controlled means comprising a control rocker pivotally mounted about an axis parallel to the drive axis of the blade and having a first end forming a ramp for lifting the locking lever and a second end adapted to cooperate with electromagnetic means, the control lever being able to pivot between a rest position in which the ramp is distant from the locking lever and an actuating position in which the ramp comes to cooperate with the locking lever on the order of the electromagnetic means.

The aforementioned electromagnetic means advantageously comprise an electromagnet (also called "electromagnetic suction cup") capable of holding the control rocker in the rest position and of releasing the control rocker to bring it to its actuation position.

These electromagnetic means can be chosen from an electromagnetic suction cup and an electromagnetic emission suction cup.

According to another characteristic of the invention, elastic return means are connected to the control lever to urge it towards its actuating position.

Thus, when the control lever is released, it is biased towards its actuating position, which lifts the locking lever and allows the locking finger to pass from the waiting position to the safety position.

The control lever advantageously has an L shape with two branches extending on either side of the pivot axis and comprising respectively the first end and the second end.

According to another characteristic of the invention, the locking finger has its own index to come into contact with the control lever, when it pivots from the standby position to the safety position, to return the control lever to its position. rest.

According to another characteristic of the invention, the device further comprises a contact rocker capable of pivoting about the drive axis of the blade and comprising two stops capable of cooperating with the locking finger respectively in its position of standby and its safety position, the contact rocker comprising an arm capable of cooperating with at least one pair of electrical contacts secured to a removable plate.

According to another characteristic of the invention, the blade drive axis comprises a shaped free end capable of being actuated by a resetting member to rotate the blade from its safety position to its standby position and thus causing the stress of the spring organ.

The reset member can be a simple key or, preferably, a servomotor coupled to the drive axis of the blade by means of a coupling.

According to yet another characteristic of the invention, the spring member coupled to the blade is a torsion spring wound around the drive axis of the blade.

In a first embodiment of the invention, the blade is a valve whose waiting and safety positions correspond respectively to the opening and closing positions of the duct.

In another embodiment, the blade is a shutter whose waiting and safety positions correspond respectively to the closed and open positions of the duct.

In the description which follows, given by way of example, reference is made to the appended drawings, in which - FIG. 1 is a view in longitudinal section of a ventilation duct fitted with a fire protection device according to the invention , in which the blade is a fire damper in the standby position (duct opening position); - Figure 2 is a top view of the device according to the invention after removal of the booster; - Figure 3 is a side view corresponding to Figure 2; - Figure 4 is a top view of an operating part of the blade; - Figure 5 is a top view of the locking lever; - Figure 6 is a side view of the locking latch of Figure 5; - Figure 7 is an end view of the locking lever of Figures 5 and 6; - Figure 8 is a top view of the control lever; - Figure 9 is a top view of the contact rocker; and - Figure 10 is a top view similar to that of Figure 2, the device being shown in its safety position (blade closed position).

First of all, reference is made to FIG. 1 which represents a ventilation duct 1 of generally rectangular section comprising in particular an upper wall 2 and a lower wall 3. The duct 1 internally houses a blade 4, in the example a valve, of generally rectangular shape provided with two pivots 5 and 6 cooperating respectively with bearings 7 and 8 housed in the walls 2 and 3.

On the upper wall 2 of the duct is placed a housing 9 provided with a removable cover 10 on which an actuator 11 is placed externally. This servomotor comprises a coupling 12 cooperating with an upper end 13 of a drive axis 14 which passes through the wall 2 and which extends parallel to the pivot axis XX of the blade 4.

The conduit 1 passes through a wall M and the device is arranged so that the pivot axis XX of the blade 4 is in the thickness of the wall, while the drive axis 14 and the housing are offset to outside the wall M.

The drive shaft 14 has a lower end 15 which projects inside the conduit and on which is fixed a lever 16 provided with a roller 17 adapted to move in an inner cam (23) formed in a part maneuver 18 fixed to the blade 4 (Figure 4).

A torsion spring 19 is wound around the drive axis 14 and it has two ends 20 and 21 bearing respectively on the housing 9 and on the lever 16.

The spring 19 is capable of being prestressed under the action of the servomotor 11 by rotation of the axis 14 by a quarter turn from the position shown in FIG. 1 in which the lever 16 is parallel to the axial direction YY of the conduit 1 (blade 4 in the open standby position) to another position in which the lever 16 is perpendicular to the direction YY (blade 4 in the closed safety position, as shown in broken lines by the reference 4 ').

In the standby position shown in Figure 1, the spring 19 is prestressed and the lever 16 is held in this standby position by locking means which will now be described.

The axis 14 is provided with a locking finger 22 of square section (Figures 1 and 2) which extends radially with respect to the axis XX and which is housed inside the housing 9. The finger 22 comprises a free end 24 which, in the standby position (FIGS. 1 and 2), is retained by a locking lever 25. As a variant, the locking finger 22 can be provided with a rolling roller placed at the free end 24 to facilitate cooperation with the locking lever 25.

The locking lever 25 (Figures 5 to 7) is a part made from a metal sheet folded in a U and having a core 26 and two wings 27 and 28. The wing 27 is extended laterally by an actuating tongue 29, while the wing 28 has a ramp 30 leading to a notch 31 capable of receiving the free end 24 of the finger 22.

The tongue 29 protrudes outside the housing 9 and thus allows manual movement of the locking latch 25 if necessary. The locking lever 25 is pivotally mounted about an axis 32 (Figure 2) carried by a support 33 fixed on the bottom of the housing 9 and extending in a direction orthogonal to the drive axis 14 of the blade .

As a result, the locking lever 25 is hinged directly to the housing 9.

The locking lever 25 is biased by a spring 34 (Figure 6) towards the bottom of the housing, in a position where the core 26 extends parallel to the bottom of the housing. The locking lever can then keep the blade in the standby position, by cooperation of the end 24 of the finger 22 with the notch 31 (position shown in FIG. 2).

In order to be able to move the blade from its standby position to its safety position (FIG. 10), control means are provided for lifting the locking lever 25 and thus allowing finger 22 to pivot a quarter of a turn under the action of the spring 19 preloaded beforehand.

In a simplified version of the device of the invention, the control means comprise a thermal fuse 35 housed in the duct 1 and coupled to a pusher 36 provided with a helical spring 37. The fuse 35 is removable from the outside and crosses the wall 2 of the duct and has a lower part 38 capable of melting from a given temperature threshold (for example 70 "C) to release the spring plunger 36. In such a case, the plunger 36 moves parallel to the axis 14, in the example vertically upwards, and causes the raising of the locking lever 25 and the release of the finger 22 which then pivots by a quarter of a turn.

Self-controlled means are thus produced which allow the blade to pass from its standby position to its safety position, as soon as the temperature detected in the duct 1 reaches a given threshold.

To reset the device and move the blade from its safety position to its standby position, the axis 14 must be pivoted a quarter of a turn in the opposite direction.

This rotation can be carried out either by means of a simple key (not shown) acting on the end 13 of the axis, or preferably by the servomotor 11. In such a case, the servomotor is actuated from a quarter turn to ensure the rotation of axis 14.

The servo motor comprises a motor with mechanical reversibility which allows the valve to pass from its standby position to its safety position under the action of the spring 19 with a very low resistive torque.

When the finger 22 is moved from the safety position to the standby position, its end 24 engages against the ramp 30 of the locking lever 25 (FIG. 6) and then comes to be housed in the notch 31 of the lever .

The device shown in the drawings also includes remote-controlled means to allow the device to be unlocked by lifting the locking lever 25.

These remote-controlled means comprise a control lever 40 (FIG. 2) pivotally mounted around an axis 41 parallel to the drive axis 14. This lever 40 (FIG. 8) has an L shape and comprises a first branch 42 terminated by a ramp-shaped end 43 and a second branch 44 terminated by a contact plate 45 capable of cooperating with an electromagnet 46 (FIG. 2). In the example, this electromagnet is an electromagnetic rupture cup. The control lever 40 is able to pivot between a rest position (FIG. 2) in which the ramp 43 is distant from the locking lever 25 and an actuation position (not shown) in which the ramp 43 comes to cooperate with the locking lever to lift it. The ramp 43 is in fact shaped to cooperate with the lower face of the core 26 of the locking lever 25, on the side of the core 26 opposite its axis of articulation. The locking lever is shown in its two positions in FIG. 3.

The control lever 40 is held in its standby position by the electromagnet 46. A return spring 47 (FIG. 2) is interposed between the housing and the branch 42 of the control lever 40 to urge the latter towards its actuation position. The control lever 40 is held in the standby position by cooperation of the contact plate 45 and the electromagnet 46.

It is possible to remotely control the unlocking of the device by acting on the electromagnet 46, which releases the contact plate 45 and makes the control lever 40 pivot under the action of the spring 47 and then causes the lever to lift. 25 and the release of the locking finger 22.

The latter is equipped with an index 48 provided with a roller (not shown) (Figure 2) which is adapted to cooperate with a ramp 49 provided on an inner face of the branch 42 of the control lever 40 (Figure 8) . When the finger 22 passes from the standby position (FIG. 2) to the safety position (FIG. 10), the index finger 48 comes to cooperate with the ramp 49 to bring the control lever 40 back into its standby position, in which the contact plate 45 cooperates with the electromagnet 46, which allows the device to be ready for a new operating cycle.

The device also comprises a contact rocker 50 suitable for pivoting around the drive axis 14. The contact rocker 50 (FIG. 9) is produced from a cut and folded sheet metal and has a hole 51 for the passage of the axis 14. It further comprises a substantially radial arm 52 which carries a contact plate 53 suitable for cooperating with two electrical contactors 54 and 55 (FIG. 2).

Furthermore, the contact lever 50 has two stops 56 and 57 capable of cooperating with the locking finger 22, respectively in its standby position and its safety position. When the locking finger 22 is in its standby position (Figure 2), the plate 53 cooperates with the contactor 54 and, when the finger 22 is in its safety position (Figure 10), the plate 53 cooperates with the contactor 55. The contactors 54 and 55 constitute position signaling means, giving information on the position of the blade 4.

In the standby position the contactor 54 is actuated and, in the safety position, the contactor 55 is actuated.

As can be seen in FIG. 2, the housing 9 also houses a terminal block 56 capable of being connected, on the one hand to an electrical power source and to a remote control and, on the other hand, to the various organs of the device (servomotor 11, electromagnet 46 and contactors 54 and 55).

Terminal block 56 and contactors 54 and 55 are integral with a removable plate 58 (Figure 10).

The device of the invention is easy to access, since the drive axis 14 is offset relative to the pivot axis XX of the blade 4 (Figure 1). It follows that the housing 9 and the actuator 11 are located outside the wall M through which the duct 1 passes (FIG. 1). This facilitates maintenance and regulatory verification operations, the actuator 11 and the cover 10 being easily removed.

It should be noted that the device of the invention can be produced in a basic version, called "self-controlled", in which the unlocking is carried out by means of the fuse 35 and the reset is carried out using a key cooperating with the end 13 of the drive shaft 14. It is possible to provide more advanced versions by then adding the control lever 40 with the electromagnet 46 and / or the contact lever 50 with the contactors 54 and 55. Likewise, it is possible to subsequently provide the booster 11, the positioning of the motor being effected by simple introduction of the free end 13 of the axis 14 into an appropriate housing of the transmission 12. To avoid any insertion error, the end 13 is advantageously provided with a polarizing device (not shown).

Of course, the invention is not limited to the embodiment described above by way of example and extends to other variants. Thus, as already indicated, the blade 4 can constitute a smoke extraction flap whose waiting and safety positions are respectively closed and open. Also, the electromagnet actuating the control rocker 40 can be not only a suction cup, but also an emission suction cup.

Claims (14)

Claims 1. Firestop device for ventilation duct, comprising a blade (4) connected to a drive shaft (14) to pivot in the duct (1) between a standby position and a safety position, a spring member (19) coupled to the blade drive axis and capable of being preloaded, locking means (22, 25) capable of assuming a locked state in which the blade is in the waiting position with the member prestressed spring and an unlocked state in which the blade is urged into the safety position under the action of the spring member, and control means (35; 46) capable of acting on the locking means to bring them to the unlocked state, characterized in that the locking means comprise a locking finger (22) connected perpendicularly to the drive axis (14) of the blade (4), a locking rocker (25) pivotally mounted by compared to a housing (9) outside the c corrugated (1), about an axis (32) orthogonal to the drive axis (14) of the blade, and comprising a notch (31) suitable for retaining the locking finger (22) in the locked state and an actuating tongue (29) projecting outside the housing (9), and elastic return means (34) suitable for returning the locking lever (25) to a rest position in which the locking finger (22) cooperates with the notch (31), and in that the control means (35; 46) are arranged to act on the locking lever (25) against the elastic return means (34) to release the locking finger (22) from the notch (31) of the locking lever (25). 2. Device according to claim 1, characterized in that the control means comprise self-controlled means comprising a thermal fuse (35) housed in the conduit (1) and coupled to a pusher (36) spring (37) capable of be released and lift the locking lever (25) when the thermal fuse (35) reaches a given temperature, the thermal fuse (35) being removable and accessible from outside the duct. 3. Device according to one of claims 1 and 2, characterized in that the control means comprise remote-controlled means comprising a control rocker (40) pivotally mounted about an axis (41) parallel to the axis d 'drive (14) of the blade and having a first end forming a ramp (43) for lifting the locking lever (25) and a second end (45) suitable for cooperating with electromagnetic means (46), the control lever (40) which can pivot between a rest position in which the ramp (49) is distant from the locking lever (25) and an actuating position in which the ramp (49) cooperates with the locking lever (25) by order of the electromagnetic means (46). 4. Device according to claim 3, characterized in that the electromagnetic means comprise an electromagnet (46) adapted to maintain the control rocker (40) in the rest position and to release the control rocker to bring it to its position d actuation. 5. Device according to claim 4, characterized in that the electromagnetic means (46) are chosen from an electromagnetic suction cup and an electromagnetic emission suction cup. 6. Device according to one of claims 3 to 5, characterized in that elastic return means (47) are connected to the control lever (40) to urge it towards its actuating position. 7. Device according to one of claims 3 to 6, characterized in that the control rocker (40) has an L shape with two branches (42, 44) extending on either side of the pivot axis and comprising respectively the first end (43) and the second end (44). 8. Device according to one of claims 3 to 7, characterized in that the locking finger (22) has an index (48) capable of coming into contact with the control lever (40) when it pivots from the position waiting in the safety position, to return the control lever (40) to its rest position. 9. Device according to one of claims 1 to 8, characterized in that it comprises a contact rocker (50) capable of pivoting around the drive axis (14) of the blade and comprising two stops (56 , 57) capable of cooperating with the locking finger (22) respectively in its standby position and its safety position, and in that the contact lever (50) comprises an arm (52) capable of cooperating with at least a pair of electrical contacts (54, 55) secured to a removable plate (58). 10. Device according to one of claims 1 to 9, characterized in that the drive axis (14) of the blade comprises a free end (13) shaped, capable of being actuated by a reset member (11 ) to rotate the blade from its safety position to its standby position and thus cause stress on the spring member (19). 11. Device according to claim 10, characterized in that the resetting member is a servomotor (11) coupled to the drive axis (14) of the blade via a coupling (12). 12. Device according to one of claims 1 to 11, characterized in that the spring member (19) coupled to the blade is a torsion spring wound around the drive axis (14) of the blade. 13. Device according to one of claims 1 to 12, characterized in that the blade (4) is a valve whose waiting and safety positions correspond respectively to the opening and closing positions of the conduit (1 ) - 14. Device according to one of claims 1 to 12, characterized in that the blade (4) is a shutter whose waiting and safety positions respectively corresponding to the closed and open positions of the conduit (1) .