Abstract:
The invention relates to a fire valve made of a body ( 100 ) consisting of a frame ( 50 ) and a tunnel ( 10 ) in which a butterfly damper ( 200 ) is pivotably mounted between a closed position, separating an inner side (I) from an outer side (E), and an open holding position. The body ( 100 ) and the butterfly damper ( 200 ) formed by a blade ( 210 ) are each produced by assembling cut and pasted refractory sand-lime plates ( 11, 51, 211 ). The assembly forming the body ( 100 ) and that forming the butterfly damper ( 200 ) are provided with steel reinforcements directly attached to the plate assemblies. The reinforcements ( 60, 70 ) of the body ( 100 ) are attached onto the outer side of the tunnel ( 10 ) and of the frame ( 50 ) and the reinforcements ( 240, 250 ) of the butterfly damper ( 200 ) are attached onto both sides of the blade ( 210 ). The butterfly damper is locked by the expansion of the metal elements.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a U.S. National Phase Patent Application based on International Application Serial No. PCT/FR2010/050520 filed Mar. 23, 2010, which is based on French Patent Application No. 0952318 filed Apr. 9, 2009, the disclosures of which are hereby explicitly incorporated by reference herein. 
     BACKGROUND OF THE INVENTION 
       1 . Field of the Invention 
     The present invention relates to a fire stop valve which is formed by a member composed of a frame and a tunnel, in which a butterfly damper is mounted for pivoting about an axis between a closed position restoring the fire retardant rating of a wall or a panel and an open position called the standby position. 
       2 . Description of the Related Art 
     There are many types of fire stop valves which are generally of complex construction in order to be able to withstand the temperatures and pressure differences imposed by some regulations. The complexity of existing valves is made necessary by their structure itself, which transmits the increase of temperature in the chamber to be isolated from the exterior, bringing about expansions, and deformations reducing the fluid-tightness of the valve in the closed position. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to develop a fire stop valve which ensures, for a very long period of time, effective separation between the space to be protected and the exterior whilst using simple means which do not involve prohibitive costs. 
     To that end, the present invention relates to a fire stop valve of the type defined above, characterised in that the member of the valve and the butterfly damper allow effective thermal insulation between the inner side and the outer side which the valve has to separate in the closed position. That thermal insulation which prevents practically any thermal bridge without thereby weakening the butterfly damper effectively ensures that the interior is cut off and is separated in a sealed manner for a very long period of time under the conditions imposed on such valves. 
     In spite of the absence of a direct metallic connection between the inner side and the outer side which are separated by the fixed and movable parts of the valve, the valve effectively withstands the pressure difference which must be applied to it. 
     That structure of the fire stop valve does not complicate its construction, its installation or its actuator. 
     According to an advantageous feature, the refractory plates are silicocalcareous plates. 
     According to another advantageous feature, the tunnel is formed by walls which are composed of a plurality of layers of refractory plates which are arranged on edge and the tunnel is mounted on the frame formed by the combination of adhesively bonded plates in a flat state, and the frame carries an abutment belt having an L-like cross-section, of which one branch is fixed in a flat state, at the outer side, to the frame and the other branch surrounds the tunnel, the valve being fixed around the opening to be protected by means of bolts which adjoin the abutment belt. That allows the member of the valve to be constructed, that is to say, the tunnel and the frame thereof, by assembling cut plates which confer on the assembly a stronger, stratified structure than construction from plates having a single thickness. Furthermore, this facilitates the assembly between the tunnel and the frame. 
     According to another advantageous feature, the tunnel comprises, at the outer side, an external steel frame which is bent into a U-shape and which is fixed to plates carried by the external wall of the tunnel, the external frame having extensions in the form of limbs which are received in openings of the plates. That construction allows the expansile portions to be disengaged from the portions having a small expansion coefficient, that is to say, the portions of the valve constructed from refractory plates, in particular from silicocalcareous plates. 
     According to another advantageous feature, the butterfly damper is in the form of a panel composed of the assembly of refractory plates, the assembly carrying two axial elements which are received in bearings of the tunnel, the two faces of the panel are reinforced by corner members which are perpendicular to the pivot axis and the two faces of the panel are reinforced in the region of the pivot axis by two bands which receive the plates of the panel in a sandwich-like manner and are fixed to the axial elements by bolts which extend from one side to the other through the assembly which is formed by the first band, the plates, the axial element and the second band. That construction of the butterfly damper affords the advantages of a thermal cutoff whilst having sufficient strength to withstand the pressure difference applied between the two faces of the valve. 
     According to a particularly advantageous feature, the corner members reinforcing the two faces of the panel of the butterfly damper are mounted by means of screws in oblong holes of the corner members on the faces of the panel in order to allow them to freely expand and in the region of the position of the ends of the corner members, the butterfly damper being closed, the interior of the tunnel is provided with latching plates which receive the end of the corner members when the corner members are extended by the expansion brought about by a temperature increase. That construction effectively joins the butterfly damper to the member of the valve, in the closed position, that is to say, in the active position, without any motor-driven mechanism in order to ensure that locking in a closed position because the locking is carried out by the expansion of the corner members which necessarily occurs, at least at the side exposed to the fire. 
     According to another advantageous feature, the interior of the tunnel is provided, at the inner side of the valve, with an upper seat and, at the outer side, with a lower seat, against which the panel of the butterfly damper moves into abutment in the closed position, those abutment actions being complemented by left and right, upper and lower half-seats. Those abutments, which are simple to construct, simultaneously ensure thermal insulation, with the creation of thermal bridges being prevented, and the reinforcement of the closed position of the valve. 
     According to another advantageous feature, one of the axial elements is connected to an actuator fixed to a bearing. 
     In order to ensure the sealing between the wall of the tunnel and the panel of the closure member  210 , an axial washer of silicocalcareous material is fitted on the damper on each of the axial elements in order to receive, in a groove, the thickness of the closure member and to be repelled towards the inner wall of the tunnel by compression springs which are received in the closure member. 
     According to another advantageous feature, the butterfly damper is in the form of a panel which is composed of the assembly of refractory plates, the assembly carrying two axial elements which are received in the bearings of the tunnel, the bearings are each formed by a plate which is provided with a clip which is coaxial relative to the axis of the damper in order to abut the outer face of the tunnel, the clip being received in a chamber of the tunnel and the clip receives a graphite ring which is retained by a seal-carrying ring, the assembly being capped externally by a planar joint which is covered by a closure plate or by the casing of the actuator. 
     According to another advantageous feature, the abutment belt is formed by corner members which have L-shaped cross-sections and which are mechanically imbricated in the region of the corners in order to allow them to expand freely. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be described below in greater detail with reference to one embodiment of a fire stop valve illustrated in the appended drawings, in which: 
         FIG. 1  is a top view of the outer side of the fire stop valve according to the invention, 
         FIG. 2  is a cross-section according to plane  11 - 11  of  FIG. 1 , 
         FIG. 3  is the sectional view of  FIG. 2  drawn to an enlarged scale, 
         FIG. 4  is an axial section of the two bearings of the damper and 
         FIG. 5  is a sectional view, drawn to an enlarged scale, of a bearing of the butterfly damper (the one not carrying the actuator). 
     
    
    
     DETAILED DESCRIPTION 
     According to  FIGS. 1 and 2 , the invention relates to a fire stop valve which is formed by a member  100  composed of a frame  50  and a tunnel  10 , in which a butterfly damper  200  is mounted. The butterfly damper  200  is carried by two axial elements about a pivot axis (xx) which is generally horizontal when the valve is installed. The valve is controlled by an actuator  300  which ensures its closure movement; it is combined with a rearming lever  301  and optionally with a closure security member  302  which allows the valve to be closed in the event of detection of an excessive temperature increase, in the region of the valve, and independently of a signal sent by the central control unit to the actuator  300 . A manual control unit  303  allows closure tests to be carried out. Rearming is carried out by means of the lever  301 . 
     The butterfly damper  200  of the valve is actuated by the return torque of a spring or an equivalent element of the actuator  300 . That return torque is released by the actuator  300 , the security device  302  or the manual control unit  303 . 
     According to  FIG. 2 , the member  100  and the butterfly damper  200  are constructed by assemblies of plates of a refractory material, in particular silicocalcareous plates which are composed of a mixture of silica and calcium carbonate, which has the advantage of being refractory. Those plates are cut and adhesively bonded to each other by an adhesive which is also refractory; the member  100  of the valve and its butterfly damper  200  are provided with reinforcements of sheet steel, which may be flat or bent and which are located at the outer side for the member  100  and on the two faces of the butterfly damper  200 . 
     It will conventionally be understood in the description that the inner side (I) is the side of the valve exposed to heat and the outer side (E) is the side located at the other side of the valve, which side must be separated in a sealed manner by the fire stop valve with respect to the inner side. 
     In greater detail according to  FIGS. 1 and 2 , the member of the valve  100  is composed of the tunnel  10  and the frame  50 . The peripheral wall of the tunnel  10 , which delimits a rectangular or square opening (OV), is formed by the assembly of silicocalcareous plates  11  which are adhesively bonded to each other in the flat state, for example, two layers of plates  11 . The tunnel  10  is carried by the frame  50  which is also composed of silicocalcareous plates  51  which are cut, adhesively bonded to each other in the flat state and also adhesively bonded at the inner edge  12  of the tunnel  10 . The frame  50  is intended to be pressed against the wall P which bounds the opening OV which is intended to be closed by the fire stop valve. 
     The assembly of the tunnel  10  and the frame  50  is reinforced by an abutment belt  60  which is constituted by the assembly of four corner members  61  having an L-shaped cross-section, of which one branch  62  is fixed in the flat state against the abutment frame  50  and the other branch  63  is pressed against the outer face of the tunnel  10 . The branch  62  pressed against the frame  50  is fixed thereto by retention screws  65  which extend only slightly into the thickness of the plates  51  of the frame without extending therethrough. 
     Openings  52  and bolt-holes  64  are provided in the frame  50  and in the abutment belt  60  in order to bolt the member  100  of the valve to threaded rods which are carried by the wall P. Those rods are not illustrated. 
     As shown by  FIG. 1 , the abutment belt  60  is composed of four corner members  61  which are connected at the corners  66  (one of the zones is surrounded by a circle) without being fixedly joined to each other so as to allow free expansion play of those four corner members  61  under the effect of a temperature increase in order to keep the fire stop valve sealed for the time fixed by provisions. 
     According to  FIGS. 2 and 3 , the outer edge  13  of the tunnel  10  is bounded by an outer steel frame  70  which is formed by a metal profile-member which is bent into a U-shape, of which one branch  71  is pressed against the edge  13  of the tunnel and the other branch  72  is free. 
     The assembly between the outer frame  70  and the tunnel  10  is brought about by means of limbs  73  which are carried by the branch  71  of the frame. Those limbs  73  protrude towards the outer side of the contour of the frame  70  in order to freely engage in the direction of expansion in oblong openings  76  which are constructed in plates  75  which are connected by screws  77  against the outer wall of the tunnel  10 . 
     The butterfly damper  200  is formed by a panel  210  which is composed of silicocalcareous plates  211 . That panel  210  or more generally the butterfly damper  200  is mounted for pivoting about the geometric axis (xx) which is defined in the plane of  FIG. 1  and which is perpendicular to the plane of  FIG. 2 . 
     According to the geometric axis (xx), the panel  210  carries two axial elements  220 ,  221  which are received in bearings  230 ,  231  which are fixed to the tunnel  10  which forms the frame of the butterfly damper  200 . 
     The axial element  221  cooperates with the actuator  300  which is fixed to the side of the tunnel and is connected by nesting and form-fitting connection. 
     The outer face and the inner face of the panel  210  are reinforced by corner members  240  which have an L-shaped cross-section and which are fixed by a branch  241  in the flat state against each of the two faces of the panel  210 . That fixing is carried out by interposing on each face a band  249  which is aligned in accordance with the pivot axis (xx). The excess thickness brought about by the band  249  is compensated for at the other two fixing locations  243 ,  244  of each reinforcement corner member  240  by a washer  245  having the same thickness as the bands  249  ( FIG. 3 ). Furthermore, in the region of the two fixing locations  243 ,  244 , each corner member  240  is fixed to the panel  210  by a screw  246  which extends through an oblong hole  247  and also the washer  245  forming the thickness spacer. 
     The assembly of the panel  210  of the butterfly damper and the axial elements  220 ,  221  thereof is carried out by means of bolts  260  which extend through the bands  249 , the thickness of a plate  211 , the axial element  220 ,  221  in order to extend back through the other plate  211  and the other band  249 . Some bolts  260  also extend through the two corner members  240  at one side and the other of the panel  210 . 
     According to the view of  FIGS. 2 and 3 , the ends of the branches  242  of the corner members  240  which are perpendicular to the surface of the plate  210  have projections  248  which are intended to cooperate with latches  270 ,  271  which are carried by the tunnel  10  at a location opposite the projections  248  when the butterfly damper  200  is in a closed position. 
     The latch  270  is a steel plate which is screwed by screws  272  against the inner surface of the tunnel  10 . 
     The other latch  271  is a piece of bent sheet metal which is screwed by screws  273  directly against the inner surface of the tunnel  10  and the portion of the latch  271  bent into a perpendicular shape is screwed by screws  274  with a lower/upper seat  280 ,  281  being interposed for the upper edge and the lower edge of the panel  210 . 
     The seats  280 ,  281  are complemented by left, right, upper and lower half-seats  282 , 283 . 
     In a closed position and at ambient temperature, the projections  248  of the corner members  240  are spaced apart by the distance (e) from the latches ( 270 ,  271 ), which allows the projections to pass and the panel  210  to move in a pivoting manner. Under the effect of heat, however, expansion extends the corner members  240  whose projections  248  become engaged, in some cases behind the latches  270  and, in other cases, in openings  275  of the latches  271 , which not only prevents the pivoting of the panel  210  in the direction of the opening but also relieves the axial elements  220 ,  221  and the bearings  230 ,  231  thereof in respect of the thrust applied to the panel  210  by the pressure difference between the inner side (I) and the outer side (E). The upper and lower locking in the region of the latches  271  ensures securing of the plates  211  of the panel  210  and reinforces their resistance to loads. 
     According to  FIGS. 4 and 5 , since the bearings  230 ,  231  have an identical structure except that the bearing  231  opens in the actuator  300  and also carries the lever  301 , the detailed description of the portions common to the two bearings will be given only for the bearing  230 . The same reference numerals refer to the same components for the two bearings. 
     In that manner, the axial element  220  extends through a hole  14  of the first plate  11  of the tunnel  10  in order to open in the chamber  15  which is formed by the second plate  11  of that tunnel. The bearing  230  is composed of a plate  250  which is fixed against the outer side of the tunnel  10  which is fixedly joined to a clip  251  which is received in the chamber  15 . The end  222  of the axial element  220  is provided with a graphite ring  252  which is received in the clip  251  and which is retained by a seal-carrying steel ring  253  which is force-fitted in the clip  251  and which adjoins the end  222  via an O-ring  254 . The end  222  is covered by an abutment plug  255 . 
     A planar joint  256  covers the entire plate  250  of the bearing  230  and the assembly is covered by a closure plate  257  which, in the case of the bearing  231 , is replaced by the actuator  300 . 
     Inside the tunnel  10 , the axial element  220  extends through an axial washer  258  composed of a silicocalcareous material. The washer  258  comprises a groove  258 - 1  (cross-section in  FIG. 5 ), in which the thickness of the panel of the closure member  210  is fitted. 
     This axial washer  258  is repelled towards the inner wall of the tunnel  10  by two compression springs  259  which are received in the closure member  210  which prevents a gap from being able to generate a leak between the two faces of the closure member  210  whilst allowing it to rotate freely. 
     The ring  252 , which serves to ensure the guiding of the axial elements  220  and  221 , is composed of graphite. That material has been selected for its self-lubricating qualities and its excellent resistance at high temperatures. 
     The ring  252  which carries the O-ring and the planar joint  256  which covers the entire outer face of the bearing  30  allow the sealing between the interior of the tunnel  10  and the exterior to be ensured. 
     The bearing  231  differs from the bearing  230  owing to the end  224  of the square axial element  221  which is blocked in terms of rotation by form-fitting connection in the opening of an arm  304  which is carried by the actuator and which is fixedly joined to the rotary sleeve  305  which extends out of the casing  306  of the actuator and which carries the operating lever  301 . 
     LIST OF REFERENCE NUMERALS 
     
         
           10  Tunnel 
           11  Plate of tunnel 
           12  Inner edge of tunnel 
           13  Outer edge of tunnel 
           14  Hole 
           15  Chamber 
           50  Frame 
           51  Plates of frame 
           52  Openings 
           60  Abutment belt 
           61  Corner member of abutment belt  60   
           62  Branch of corner member  61   
           63  Branch of corner member  61   
           64  Openings 
           65  Screws 
           66  Corners of abutment belt 
           70  Outer frame 
           71 ,  72  Branches of frame  70   
           73  Limb 
           75  Plate 
           76  Oblong opening 
           77  Screw for fixing plate  75   
           100  Member of valve 
           200  Butterfly damper 
           210  Panel 
           211  Plates forming panel  210   
           220 , 221  Axial elements 
           222  End 
           230 , 231  Bearings 
           240  Corner member 
           241 ,  242  Branches of the corner member 
           243 ,  244  Locations for fixing the corner member 
           245  Washer forming thickness spacer 
           246  Screw 
           247  Oblong hole 
           248  Projection of corner member 
           249  Band 
           250  Plate of bearing  230 ,  231   
           251  Clip 
           252  Ring 
           253  Seal-carrying ring 
           254  O-ring 
           255  Abutment plug 
           256  Planar joint 
           257  Closure plate 
           258  Axial washer 
           258 - 1  Groove 
           259  Spring 
           260  Bolts 
           270  Latch 
           271  Latch 
           272 ,  273  Screw for fixing latches 
           274  Screw for fixing latches 
           275  Openings in latch  271   
           280 ,  281  Lower/upper seats 
           282 ,  283  Left, right, upper and lower half-seats 
           300  Actuator 
           301  Rearming lever 
           302  Closure security member 
           303  Manual control unit 
           304  Arm 
           305  Sleeve 
           306  Casing 
         xx Pivot axis 
         e Spacing 
         E Outer side 
         I Inner side 
         OV Opening in wall 
         P Wall