Patent Application
20150375024
The field of the invention is that of designing and manufacturing firefighting equipment and installations. More precisely, the invention relates to devices designated by the term “dry visor”, intended in particular for firefighting inside cold rooms.
The role of an automatic fire extinguishing installation implementing sprinklers is to detect, as early as possible, the seat of a fire then to automatically trigger the extinction system, at least locally, this while emitting an alarm. The installation has for objective to contain the fire as much as possible, before the arrival of the fire brigade which then takes over the installation in order to extinguish the fire.
In the field of the invention, firefighting installations are classified into three categories, namely:
In these three systems, the sprinklers are mounted in a network in such a way as to be distributed evenly over the site to be protected. Conventionally, the sprinklers comprise:
The fusible member is calibrated to blow when a certain temperature has been exceeded, as such releasing the nozzle from its shutoff member.
In “wet-pipe” systems, the entire piping of the installation is filled with water, and this up to the sprinklers. The water is therefore on standby behind the shutoff means and when the fusible member blows, the water flows through the nozzle of the connector of the sprinkler of which the fusible member has blown.
The release time for the water is therefore immediate, which is particularly advantageous. On the other hand, “wet-pipe” systems, are not adapted for sites that have risks of freezing. Indeed, in case of freezing, the water cannot flow. In addition, the freezing can cause deteriorations to the piping of the installation (deformation and even bursting of the pipes). In certain cases, the installation is emptied of water. In other cases, the site to be protected is heated in order to prevent any risk of freezing. For sites to be protected that have a relatively substantial surface area, the consumption of energy, and consequently the heating bill, can be substantial, and even prohibitive. Another way to fight freezing is to add an antifreeze agent to the water of the installation, such as glycol which is a toxic and carcinogenic product.
In the “dry-pipe” systems, the entire installation is emptied of water. The entire piping of the installation is kept under pressure. When the fusible members blow, the air pressure is released by the sprinkler or sprinklers in question and the water, also under pressure, tends to “push” the air outside of the installation until it arrives at the orifice or orifices released in such a way as to escape through the latter.
With such a system, the water can in certain cases take up to 60 seconds to reach the sprinkler of which the fusible member is blown, which is of course compliant with the current standard but which can be excessively long with regards certain incipient fires.
In addition, “dry-pipe” systems do not entirely overcome the problems linked to freezing. Indeed, condensation can be created in the piping of a “dry-pipe” installation, which can damage certain components of the installation and cause the protection to fail.
Generally, “wet-pipe” and “dry-pipe” systems have the following disadvantages:
This results in that they require, among other things, antifreeze and anticorrosion treatments (involving recourse to harmful products).
Moreover, they require rinsing operations after use.
Furthermore, they imply putting into service times that are relatively long, according to the extent of the installation, which can range from one to four hours for “wet-pipe” systems and two hours and more for the “dry-pipe” systems.
In order to overcome all of these disadvantages, “vacuum” systems were designed. In “vacuum” systems, a vacuum is created in the pipes extending between a general valve and all of the sprinklers. In other terms, all of the pipes separating the valve from the sprinklers are in a vacuum.
In these systems, the vacuum constitutes an active energy which is used as a functional source in monitoring sprinklers. Indeed, if a fusible member of one of the sprinklers blows, the atmospheric pressure reaches the entire installation, which causes a change in the state of an actuator which, in turn, opens the general water inlet valve. Then the water quickly and without any obstacle invades the entire installation until the sprinklers, with the water flowing through the sprinkler or sprinklers of which the fusible member has blown. The vacuum which is still active in the networks quickly attracts the extinguishing water towards the sprinklers of which the fusible member has blown.
The triggering time of the actuator is very short, in that, when a fusible member blows, the “vacuum” installation immediately generates an aspiration phenomenon of the air outside of the installation. Note that this aspiration can be beneficial, as the aspiration effect on the seat of the fire tends to reduce the intensity of the latter.
The time for the water to arrive at the sprinkler of which the fusible member has blown is less than 60 seconds.
It is therefore understood that, due to the absence of water or of condensation in a “vacuum” system installation, the following results are obtained:
For certain installations, it is necessary to plan for the implementation of dry visors, used for fighting a fire that can break out in a cold room.
These dry visors provide the connection between a pipe of the network of “vacuum” sprinklers and the inside of the cold room. For this, the dry visors have an elongate body having at one of its ends a connecting piece for coupling to pipework and, at the other of its ends, a sprinkler of the type of that described hereinabove.
The height of the elongate body is sized according to the thickness of the thermally insulated wall of the ceiling of the cold room.
Of course, this size of the elongate body is such that the sprinkler borne by the lower end of the dry visor extends into the internal volume of the cold room.
The design of dry visors is provided in such a way that, when the network of sprinklers is filled with water, the dry visors for which the fusible members have not blown are not filled with water. Indeed, even after the network of sprinklers is placed in a vacuum, water could stagnate in the elongate body of a visor and, in light of the temperature in the cold room, would freeze. This would result in a failure of the visor in the situation of a fire inside the cold room for one and/or the other of the following reasons:
In order to prevent this situation, dry visors include means of shutting off the connection, constituted by a first nozzle, between the visor and the pipework that bears it.
According to the operation of this dry visor, if the fusible member of the sprinkler of the visor blows, the shutoff valve on the sprinkler is ejected, which drives the displacement of the shutoff means on the first nozzle, in such a way as to release the communication between the visor and the pipework bearing the visor.
On the other hand, if the fusible member of the sprinkler of the visor does not blow, the shutoff means on the first nozzle remain in shutoff position and isolate the visor from the water present in the network of sprinklers.
However, according to the design of current visors and the corresponding maintenance practices, when the sprinkler of a dry visor has been triggered, the latter is entirely replaced.
As the cost of a single dry visor is relatively substantial, this maintenance practice is particularly expensive when it is a question of replacing all of the dry visors of a cold room.
Moreover, the sprinklers present at the mower end of the dry visors, as with all the other sprinklers of a “vacuum” network, comprise, in addition to the fusible member and the shutoff member, means for ejecting the shutoff member.
Indeed, as indicated hereinabove, when a fusible member blows, this results in an aspiration phenomenon of the air towards the inside the pipework of the installation. The shutoff member, if it is not forced to leave its location, remains somewhat “glued” on the mouth of the nozzle of the connector, which then does not allow the air to enter and consequently prevents the actuator from being triggered.
In order to prevent this, means for ejecting are mounted on each sprinkler. These means for ejecting are conventionally constituted of a spring inserted into a cylindrical part mounted in the nozzle of the sprinkler. An end of the spring is bearing against the bottom of the cylindrical part, while the other spring end is bearing against the shutoff valve held in position by the fusible member. The spring is of course in compressed state.
With such sprinklers, undesirable situations have sometimes been observed.
Indeed, it was observed that after blowing of the fusible member, the shutoff valve can remain in a partial shutoff position of the nozzle of the connector or in a position that hinders the proper distribution of the water. In any case, the spring is not ejected from the nozzle and therefore remains inside the latter.
This results in that, in any case, the nozzle is not entirely released, which forms a partial obstacle to the intake of air in the network. The consequence is that the vacuum of the installation is slowed down and, consequently, the triggering of the actuator is delayed, which can reach 30 to 40 seconds.
An exemplary embodiment of the present disclosure relates to a dry visor intended to be mounted in a firefighting installation, of the type comprising a network of vacuum sprinklers, with the visor comprising an elongate body having at one of its ends a connecting piece for coupling to pipework, including a first nozzle able to provide the connection between the visor and the pipework, with the visor including means for shutting off the first nozzle; with the other end bearing a sprinkler comprising:
As such, with a visor according to the invention, when the latter must be put back into service after the fusible member of the sprinkler of the visor has blown, it is not necessary, contrary to prior art, to replace the entire visor.
Indeed, with a visor according to the invention, it is possible to replace only the sprinkler, and even only the fusible member of the sprinkler.
As it shall appear more clearly in what follows, the putting back into place of a sprinkler with a new fusible member will act on the means of connection between the shutoff means that shut off the first nozzle and the shutoff member that shuts off the second nozzle, in such a way that the means for shutting off the first nozzle are automatically in service once the new sprinkler is installed.
It is understood that when changing only the sprinklers, and even only the fusible members of the sprinklers, relatively substantial gains can be obtained on maintenance costs.
Furthermore, with a visor according to the invention, the maintenance operations can be executed easily and very quickly.
In addition, the means for evacuating water are provided, as shall be explained in more detail in what follows, in order to evacuate the water introduced into the elongate body of the dry visor due to slight leaks.
Furthermore, thanks to their structure, the means for evacuating water are simple and act effectively and naturally according to the quantity and the water pressure in the dry visor, and this in the following way:
According to an advantageous solution, the means for connecting include a shaft, with the body of the visor including means for guiding said shaft in longitudinal translation.
In this case, the means for shutting off the first nozzle are advantageously secured with an end of said shaft.
Furthermore, the means for guiding preferably comprise at least one intermediate part between two sections of the body of the visor, with the part being punched and having central slide inside of which the shaft is guided in translation.
As such, the guiding in translation of the connection shaft is provided, and this while producing a dry visor constituted of the assembly of spare parts that are simple in design and inexpensive to produce.
Preferentially, at least one spring is mounted between a means for stopping on the shaft and the intermediate part, with the mounting of the spring being carried out in such a way that the spring is in compression in the shutoff positions of the shutoff member and means for shutting off the first nozzle.
Such a mounting will contribute to the reactivity of the dry visor in case the latter is triggered due to the blowing of the fusible member of its sprinkler.
In addition, the shaft advantageously bears a stop intended to bear against an intermediate part and to retain the shaft when the shutoff member and the means for shutting off the first nozzle are not in shutoff position.
According to a particular embodiment, said end section is connected to another section of the body by a punched intermediate part and having a central slide inside of which the shaft is guided in translation. In this way, two different guiding zones of the connection shaft inside the elongate body of the dry visor can be obtained.
According to another advantageous characteristic of the invention, the means for ejecting the shutoff member from the sprinkler are mounted outside the second nozzle and act in a pulling sense on the shutoff member.
As such, thanks to this characteristic, after the blowing of the fusible member of a sprinkler of a dry visor according to the invention, the complete release of the nozzle from the sprinkler in question is obtained.
Indeed, two characteristics of the invention are combined in order to obtain this particular advantageous result, namely:
Other characteristics and advantages of the invention shall appear more clearly when reading the following description of a preferred embodiment of the invention, given by way of a simple example for the purposes of information and non-restricted, and of the annexed drawings among which:
Such as shown in
The connecting piece 50 is intended to allow the connecting of the dry visor to pipework, and includes in order to do this a first nozzle 51 able to provide the connection between the visor and the pipework. The dry visor furthermore includes means 60 for shutting off this first nozzle 51, with these means for shutting off being mobile between a shutoff position of the nozzle 51 (
The sprinkler borne by the dry visor according to the invention is of the type comprising:
The fusible member 2 bears, by one of its ends, on the shutoff member 3 in such a way as to maintain the second nozzle in its shutting-off position, with the other end of the fusible member bearing against a lug 20 integral with the yoke and, here, with the deflector 12 (with the lug 20 being in practice also a means of fastening by screwing of the deflector on the yoke).
In the standby position of a visor such as shown in
According to the principle of the invention, the dry visor comprises means of connection 6 between the shutoff means 60 that shut off the first nozzle 51 on the one hand, and on the other hand, the shutoff member 3 that shuts off the second nozzle 10, with these means of connection being mobile in such a way as to cause the shutting-off position of the shutoff member 3 to coincide with the shutting-off position of the shutoff means 60 of the first nozzle 51.
According to this embodiment, the means of connection 6 comprise a shaft extending inside the elongate body of the visor, and on the end of which are secured the shutoff means 60 for shutting off the first nozzle 51.
The end of the shaft constituting the means of connection and provided with a thread, and the shutoff means 60 are comprised of a head having a bore, in such a way that the head of the shutoff means is screwed to the corresponding end of the shaft.
At its other end, the shaft has a cup 61 intended to bear, as shown in
Inside the elongate body 5, the shaft of the means for connecting is guided in longitudinal translation, and this using means for guiding that comprise, such as shown in
Note that the elongate body 5 of the visor is constituted by the assembly of the following parts:
Such as shown in
In addition, the means of connection bear a stop 63 intended to bear against an intermediate part, here the intermediate part 53, this to retain the shaft when the shutoff member 3 and the means for shutting off 60 are not in shutoff position (
Moreover, the end section 56 has means for evacuating water comprising:
The cap 562 itself has a cavity that communicates with the duct 560, and extends in the continuity of the duct 560 with the same inclination.
On the internal side of the end section, the cap 560 has a grid for retaining the ball, through which water can flow. An orifice passes through the head of the cap 560 making it possible to evacuate the water towards the outside of the end section.
As such, in the absence of pressure, the ball is at the bottom of the cavity of the cap (with the ball having a diameter that does not obstruct the passage of water in the bottom position in the cavity of the cap).
In addition, the system of the means for evacuating according to the invention is advantageous in the case of slight leaks between the visor and the duct to which it is connected. Indeed, in the presence of slight leaks (which will not trigger the installation which is provided for in order to re-establish the vacuum in case of leaks that are lower than a predetermined level), the visor will make it possible, through the bottom position of the ball which allows for air to pass to the outside end of the inclined duct, an aspiration that tends to evacuate the water droplets that may be present in the visor.
On the other hand, in the presence of pressure, the ball rises against the head of the cap, and is thrust against the orifice that passes through the head of the cap in such a way as to obstruct the latter and prevent the water from flowing.
According to another characteristic of the invention, the sprinkler comprises means for ejecting mounted outside the nozzle 10 and acting in a pulling sense on the shutoff member 3. Of course, as long as the fusible member 2 is in place, the latter exerts a force that is greater than the force of the pulling of the means for ejecting.
According to this embodiment, the means for ejecting are constituted of a spring, and more precisely a torsion spring 4, such as shown in
Such as shown in these figures, the spring 4 comprises:
In untensioned state, the spring 4 has a configuration wherein the limbs 41 and 42 are separated from one another, such as shown in
Such a spring is therefore intended to cooperate via one of its limbs (here limb 41) with the shutoff member for the purpose of ejecting the latter from the sprinkler after the blowing of the fusible member 2.
According to this embodiment, the shutoff member 3 has a flange 31 extending outside the second nozzle 10 and having a flared shape.
The shutoff member 3 is kept bearing against a washer 11 mounted at the end of the nozzle 10. The flared flange 30 of the shutoff member arranges a space 110 with the washer 11.
The spring 4 is mounted on the sprinkler in such a way that one of its limbs (here the limb 41) is placed in the space 110, i.e. between the flared flange 31 and the washer 11 of the sprinkler. More precisely, the space 110 between the flange 31 and the washer 11 is provided in such a way that the corresponding limb of the spring is caught in this space once the fusible member is installed. The spring is therefore kept in complete safety in standby position.
In addition, such as shown in
The limb 41 of the spring 4 is therefore inserted into the space 110 between the flange 31 and the washer 11, while the other limb 42 of the spring 4 is kept in a means for retaining that is present on the connector, positioned in such a way that the spring takes of course its tensioned configuration such as shown in
According to this embodiment, this means for retaining takes the form of an orifice 130 arranged at the base of the yoke 13, and intended to be passed through by the limb 42 such as shown in
Moreover, according to a characteristic of the spring 4 of this embodiment, the limb 42, intended to be inserted into the orifice 130 arranged at the base of the yoke, has two portions, namely:
Such as shown in
An exemplary embodiment of the present disclosure proposes a dry visor for which the design makes it possible to limit the costs of replacement in case of triggering of the latter.
An exemplary embodiment provides such a dry visor for which the maintenance can be executed quickly and easily.
An exemplary embodiment provides such a dry visor that provides, on the sprinkler, a complete release of the nozzle from the connector in the case the fusible member blows.
In this sense, an exemplary embodiment guarantees in all circumstances a minimum triggering time of the actuator of a “vacuum” system.
Although the present disclosure has been described with reference to one or more examples, workers skilled in the art will recognize that changes may be made in form and detail without departing from the scope of the disclosure and/or the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1351518 | Feb 2013 | FR | national |
This application is a Section 371 National Stage Application of International Application No. PCT/FR2014/050284, filed Feb. 13, 2014, the content of which is incorporated herein by reference in its entirety, and published as WO 2014/128387 A2 on Aug. 28, 2014, not in English.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/FR2014/050284 | 2/13/2014 | WO | 00 |
