Abstract:
A removable casing for a fire sprinkler head encases the sprinkler head to stop unwanted water spray. The casing has hinged shells that latch closed to form a watertight interior space. One or both of the shells have gaskets that contact the opposite shell to seal off the interior space. The hinges and latches may be adjustable to make the casing easier to fit over the sprinkler head and to fasten tightly. Each shell may have one or more necks configured to fit tightly around a pipe when the casing is closed. A drain having a valve may be disposed through one or both of the shells to prevent initial pressure buildup and to allow the removal of accumulated water from inside the casing. The casing fills with water until the flow out of the sprinkler head stops, allowing the rest of the fire sprinkler system to remain active.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a non-provisional and claims the benefit of U.S. patent application Ser. No. 61/473,103 filed Apr. 7, 2011 and incorporated herein by reference. 
    
    
     FIELD OF INVENTION 
     This invention relates to fire sprinkler control devices. This invention relates particularly to an apparatus for encasing a damaged or malfunctioning fire sprinkler head to stop the flow of water out of the head while allowing the remainder of the sprinkler system to stay active. 
     BACKGROUND 
     A structural fire sprinkler system is composed of fire sprinkler heads that spray water into the structure interior, a series of supply pipes that deliver water under pressure from a water source to the sprinkler heads, and various types of controls for determining response parameters and starting or stopping the flow of water. Typical sprinkler heads detect a fire in the vicinity with a heat-sensitive plug that fails at a certain temperature. In a “wet” system, the water is retained under pressure in the supply pipes at the mouth of the sprinkler heads, such that the plug is the only impediment to the water being released at high velocity from the sprinkler head. Thus, upon failure of the plug, the sprinkler head is activated and immediately begins to saturate the surrounding area. 
     Unfortunately, typical plugs are susceptible to damage or dislocation due to unintended contact, such as bumping during a construction project, or other unwanted mechanical failure. The immediate emission of water after a plug failure is good for suppressing fires, but causes significant unnecessary water damage when a sprinkler head is simply malfunctioning. The typical response to a malfunctioning sprinkler head is to disable the entire sprinkler system, typically by turning off the system&#39;s water. However, there is usually only one valve for turning off the water, which may be far away from the malfunctioning head, hard to locate, or inaccessible without the presence of a landlord or other authorized personnel. Additionally, turning off the water leaves the building vulnerable to any actual fire that breaks out while the water is off. A device that encloses the spraying sprinkler head to limit or eliminate saturation of the surrounding area is needed. It would be advantageous for the device to be quickly and easily installed over the sprinkler head to limit water damage while allowing the fire sprinkler system to remain active. It would also be advantageous for the device to require no technical knowledge to use, so that any person who may be in the vicinity of the sprinkler head may use the device with little or no training. 
     The problem has been addressed with several devices that fit over the sprinkler head. One problem with known devices is that they must be held in place against the ceiling over the sprinkler head. Some devices must be physically held by a person, who is typically on a ladder, while others are held in tension using a pole that extends down to the floor under the sprinkler. The pole may not be usable if the sprinkler is installed in a high ceiling, or with no ceiling, or if furniture or other articles inhibit the path to the floor. A device that does not need to be propped against the ceiling around the sprinkler head is needed. 
     Another problem with known devices is that they attempt to control the flow of water by diverting it rather than stopping it. Typically, the device has an outlet that is attached to a hose or other apparatus to direct the water flowing out of the sprinkler head to a common collection area, to the sewer, or elsewhere. This is a potential waste of water and could result in water damage if there is a leak or hose damage or if the device is moved while the water is still flowing. A device that stops the flow rather than diverting it is needed. 
     Therefore, it is an object of this invention to provide a device to encase a spraying fire sprinkler head and prevent water damage from the spray. It is a further object that the device attach to the sprinkler head or supply pipe so it does not have to be propped against the ceiling or held in tension by the floor of the structure. A further object is to provide a device that stops the flow of water from the sprinkler head rather than diverting it. Another object of the invention is to provide a device that will stop the flow of water from a damaged sprinkler head without affecting the rest of the fire sprinkler system. Another object of the invention is to provide an easy-to-use device to encase a spraying fire sprinkler head. 
     SUMMARY OF THE INVENTION 
     A removable casing for a fire sprinkler head is used to prevent water damage by enclosing the sprinkler head when the sprinkler head is activated. The removable casing has first and second complementary shells that are hinged together and close to form a watertight, and preferably also airtight, interior space. Each shell may have a gasket that contacts the gasket of the other shell to form a seal when the casing is closed. One or more latches draw the shells tightly together in the closed position. The hinges and latches may be adjustable to make the casing easier to fit over the sprinkler head and to fasten tightly. Each shell may have one or more necks configured to fit tightly around a pipe when the casing is closed. A drain having a valve may be disposed through one or both of the shells to allow the removal of accumulated water from inside the casing. The drain valve may be open when the casing is placed over a malfunctioning sprinkler head in order to reduce air pressure as the seal is formed, then the valve may be closed to stop the flow of water. Once the seal is formed, the casing fills with water until water pressure equilibrium is reached, stopping the flow of water out of the malfunctioning sprinkler head. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top front perspective view of a first embodiment of the invention. 
         FIG. 2  is a bottom front perspective view of the embodiment of  FIG. 1 . 
         FIG. 3  is a top front perspective view of the embodiment of  FIG. 1  placed around a flanged sprinkler head. 
         FIG. 4  is a top front perspective view of the embodiment of  FIG. 3  closed and latched around the flanged sprinkler head. 
         FIG. 5  is a top front perspective view of the first embodiment of the invention with alternate hinges and latches, showing an exploded view of the hinging and latching mechanism. 
         FIG. 6  is a top front perspective view of the embodiment of  FIG. 5  showing the shells hinged together with the hinging mechanism. 
         FIG. 7  is a top rear perspective view of the embodiment of  FIG. 5  showing the shells hinged together with the hinging mechanism. 
         FIG. 8  is a top front perspective view of the embodiment of  FIG. 5  closed and latched around the flanged sprinkler head. 
         FIG. 9  is a top perspective view of a second embodiment of the invention. 
         FIG. 10  is a top perspective view of the embodiment of  FIG. 9  shown in relation to a direct-mount sprinkler head and supply pipe. 
         FIG. 11  is a top perspective view of the embodiment of  FIG. 9  closed and latched around the direct-mount sprinkler head and supply pipe. 
         FIG. 12  is a top perspective view of the embodiment of  FIG. 9  shown with a neck plug. 
         FIG. 13  is a top perspective view of a third embodiment of the invention shown in relation to a terminal sprinkler head and supply pipe. 
         FIG. 14  is a top perspective view of the embodiment of  FIG. 13  closed and latched around a terminal sprinkler head and supply pipe. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1-8 , there is illustrated a first embodiment of the present sprinkler head casing designated generally as  10  which is used to encase a spraying fire sprinkler head  30  and prevent water from saturating and damaging the surrounding area. The casing  10  is a latching, hinged clamshell that closes around the sprinkler head  30  and is held in place by friction fit around one or more of the components of a structural fire sprinkler system as described below. The casing  10  comprises a first shell  11  and a second shell  12 . The shells  11 ,  12  may be made of the same or a different material, which may be polyvinyl chloride or another polymer, aluminum, stainless steel, or another material that is rigid and non-permeable and does not degrade in water. The thickness of the shell  11 ,  12  walls is sufficient to withstand the water and air pressure inside the casing  10  during use. Typically, fire sprinkler systems operate under pressure of about 35-90 psi, so the shells  11 ,  12  are preferably configured to withstand at least that amount of pressure. Preferably the casing  10  is configured to withstand the maximum water pressure contained within the desired fire sprinkler system, but may be rated at higher or lower pressures if desired. As illustrated, the shells  11 ,  12  may have bands  14  of thicker material at proximal end, distal end, or both ends to provide a mounting surface for latching mechanisms as described below. 
     The general shape of the casing  10  is defined by the shape of the shells  11 ,  12 . The exterior shape of the casing  10  is preferably substantially a cylinder formed by shells  11 ,  12  that are half-cylinders. In the first embodiment, the shells  11 ,  12  are substantially identical except that the first shell  11  has a drain  17  disposed through the distal end of the first shell  11 . The shells  11 ,  12  close to define an interior space in which the sprinkler head  30  is encased. See  FIGS. 3 and 4 . The interior space should therefore be at least the size of the sprinkler head  30  and fittings to be encased. An interior space of at least about 3 inches in diameter is suitable. Preferably, however, the interior space is larger than the sprinkler head  30  and serves as a water tank, retaining the water that flows from the sprinkler head  30  until the water is emptied from the casing  10 . Each shell may have a proximal neck portion  18  formed into the proximal end that cooperates with the proximal neck portion  18  of the other shell to form a neck  40  when the casing  10  is closed. See  FIG. 4 . The neck portions  18  may have a significant height as illustrated in order to stabilize the casing  10  against the pipe, but alternatively the neck portions  18  may have no or negligible height. The neck  40  has a diameter that fits tightly around a pipe in the sprinkler system, as described below. One or more guides  27  may be disposed on the inner surface of one of the shells  11 ,  12  to align the shells  11 ,  12  with each other when the casing  10  is being closed, ensuring that the gaskets  19  make the desired seal as described below. The guides  27  may be attached to the shell  11 ,  12  with adhesive or heat bonding, or may be formed integrally with the shell  11 ,  12 . 
     Each shell  11 ,  12  may have one or more gaskets  19  attached to the surfaces of the shell that would otherwise contact the opposite shell when the casing  10  is closed. The gaskets  19  may be any flexible, impermeable material, such as rubber, elastic, or a flexible polymer. The preferred gasket  19  material is ethylene propylene diene monomer (M-class) rubber. When the casing  10  is closed, at least one gasket  19  of the first shell  11  contacts at least one gasket  19  of the second shell  12 . When the casing  10  is then latched, the gaskets  19  of opposing shells  11 ,  12  are drawn tightly together to form a waterproof seal. Thus, in the preferred embodiment, the gasket  19  of the first shell  11  is substantially complementary to the gasket  19  of the second shell  12 . It is contemplated that a single gasket  19  on one of the shells  11 ,  12  may be sufficient to complete the seal against the opposing shell, which would not have a gasket  19 . Similarly, the gaskets  19  may include one or more neck gaskets disposed in the proximal neck portions  18  of each shell  11 ,  12  to contact the pipe that the neck  40  encircles and form a watertight seal around it. Together, the gaskets  19  form a watertight seal that encases the sprinkler head  30 . Alternatively, the gaskets  19  may be formed by o-rings that fit into a groove formed into the respective surfaces to which the o-rings are attached. 
     The shells  11 ,  12  may be attached together with one or more hinging mechanisms, such as hinges  13 , but alternatively may be attached with another mechanism that allows the shells  11 ,  12  to close together as described below. For example, the shells  11 ,  12  may be integrally connected, such as through molding, by a thin portion of material that is substantially flexible to allow the shells to close together. In one embodiment, the hinges  13  are attached to the first shell  11  and second shell  12  at the rear of the casing  10  as illustrated in  FIGS. 1-4 . A hinge  13  may be any known hinge suitable for hinging the shells  11 ,  12  together in a clamshell fashion, such as a barrel, pivot, flag, or dovetail hinge. In a particular embodiment, shown in  FIGS. 5-8 , a hinge comprises a front hinge portion  13   a  attached to the front shell  11  and a rear hinge portion  13   b  attached to the rear shell  12 , the hinge portions  13   a ,  13   b  being removably attached to each other with an adjustable hinging mechanism such as the hinging mechanism illustrated in  FIGS. 5-8  and described below. Each hinging mechanism may be attached to or integral with the shells  11 ,  12  at the outer surface of each shell. In one embodiment, the hinging mechanisms are attached to a metal brace  50  that attaches to and extends laterally around the outer surface of the shell. The metal brace  50  may be adhered or non-adhesively attached to the shell. The metal brace  50  structurally supports the shell and provides a mounting surface for the hinging mechanism. 
     The hinging mechanism illustrated in  FIGS. 5-8  comprises a wingnut  60  removably attached to a bolt  62  that passes through an anchor  61 . The anchor  61  attaches to one of the hinge portions  13   a ,  13   b , preferably the rear hinge portion  13   b , and may be positioned so that the anchor  61  may pivot at or near its proximal end around an axis of rotation substantially parallel to the axis of the casing  10 . The anchor  61  may be substantially hollow or may have a channel defined from the proximal to distal end, allowing the bolt  62  to pass through it. The bolt  62  has a threaded portion  63  at its distal end and a head  64  at its proximal end. The head  64  permanently or removably attaches to the hinge portion opposite that to which the anchor  61  is attached, and thus preferably attaches to the front hinge portion  13   a . The threaded portion  63  passes through the anchor  61  and is received by the wingnut  60 , which is complementarily threaded. The shells  11 ,  12  are thus attached together, and may be disposed apart from each other or drawn tightly together by loosening or tightening the wingnut  60  on the bolt  62 . The rotation of the anchor  61  and loosening of the wingnut  60  allow the casing  10  to be opened and spread apart, facilitating the positioning of the casing  10  in use. The wingnut  60  further allows a greater degree of tightening to be applied than with a non-adjustable hinge  13 , providing more compression of the gaskets  19  together to improve the casing&#39;s  10  seal. The wingnut  60  can be removed to separate the shells  11 ,  12  from each other. 
     The casing  10  is latched using one or more latching mechanisms attached across the seam  41  between the shells  11 ,  12  at the front of the casing  10 . Any known latching mechanism capable of drawing the shells together to compress the gaskets  19  and form a seal, which is also capable of withstanding the pressure accumulated inside the casing  10 , may be used. The latching mechanism is preferably attached to the band  14  using rivets  21  or another non-adhesive attachment mechanism. Alternatively, the latching mechanism may be adhered to the band  14  or another surface of the shells  11 ,  12 , or the latching mechanism may be integral with the shells  11 ,  12 , such as by casting or molding. Preferably, two latching mechanisms are used, being positioned near opposite ends of the casing  10  to ensure a tight seal. In one embodiment, the latching mechanism comprises a draw latch  15  and a hook  16  that receives a metal loop  20  of the draw latch  15 . Such a latch draws the gaskets  19  together to compress them, and is also inexpensive and easy to use. The latch  15  is preferably secured closed using a pin  25  that passes through holes in the latch  15  to lock the latch  15  closed while the pin  25  is in place. The pin  25  may be connected to the shell with a cable  26 . 
     In an alternative embodiment, the latching mechanism comprises a bolt having a head that fits into the hook  16 , and a nut threadedly attached to the bolt to tighten the latching mechanism and draw the shells  11 ,  12  together. As shown in  FIGS. 5-8 , the latching mechanism may comprise substantially the same components as the hinging mechanism, namely an anchor  61 , bolt  62 , and wingnut  60 . The anchor  61  is attached to a bracket  65  permanently or removably attached to a shell  11 ,  12  opposite the hook  16 . The hook  16  may have a channel  66  for receiving the body of the bolt  62  such that the head  64  then fits into the hook  16  to complete the latch when the wingnut  60  is tightened down. See  FIG. 8 . Each latching mechanism may be attached to or integral with one of the metal braces  50  attached to the outer surface of the shells  11 ,  12  as described above. Preferably, one latching mechanism and one hinge are attached to each metal brace  50 . 
     A valved nozzle  22  may be attached to the distal end of the first shell  11  in fluid communication with the drain  17  in order to start and stop the flow of water from the casing  10 . The nozzle  22  is preferably threaded onto a threaded portion (not shown) of the drain  17 . The preferred nozzle  22  is therefore replaceable. Alternatively, the nozzle  22  may be adhesively attached to or integrally molded with the first shell  11 . The nozzle  22  may be any nozzle having a valve that is watertight and airtight when closed. The valve preferably has a finger-operated lever  23  that is easily manipulated by the user. The distal end of the nozzle  22  may be threaded to receive a hose for carrying the water away from the casing  10 . 
     In the first embodiment, the intended sprinkler head  30  is a flanged sprinkler head having an extension pipe  31  that extends from the water supply pipe (not shown) and ends in a flange  32  into which the sprinkler head  30  is threadedly mated. The neck  40  fits around the extension pipe  31  and has a smaller diameter than the flange  32 , so that the flange  32  abuts the interior surface of the proximal ends of the first shell  11  and second shell  12  to hold the casing  10  in place. To encase the sprinkler head  30 , a user places the first shell  11  or second shell  12  around the extension pipe  31 , as shown in  FIG. 3 , closes the casing  10  using the guides  27  to ensure the shells  11 ,  12  are aligned, and latches the casing  10 . The hinging and latching mechanisms may be tightened down to complete the seal if needed, such as in the embodiment of  FIGS. 5-8 . Preferably, the valve in the nozzle  22  is open when the user closes and latches the casing  10  so that pressure does not immediately begin to build inside the casing  10  before the casing  10  can be fully latched. The open valve keeps the pressure at equilibrium, and can then be closed once the latches are secure. 
       FIGS. 9-12  illustrate a second embodiment of the casing  10 . In the second embodiment, the intended sprinkler head  30  is directly mounted into a water supply pipe  33 . The casing  10  must therefore fit around the supply pipe  33 , which may be the same diameter or larger than the extension pipe  31 . For a supply pipe  33  larger than an extension pipe  31 , the first embodiment of the casing  10  is modified to have a wider neck  40 . The casing  10  further has a second neck  42  formed by distal neck portions  51  formed into the distal ends of each of the shells  11 ,  12 . The neck  40  and second neck  42  are aligned to allow the supply pipe  33  to pass completely through the casing  10 . The gaskets  19  may include additional neck gaskets that extend into the distal neck portions  51 . Preferably, the second embodiment comprises two gaskets  19 , each having neck gaskets in the proximal and distal neck portions  18 ,  51  of the corresponding shell  11 ,  12 . 
     The first shell  11  further comprises a branch  52  extending away from the main part of the first shell  11 , the branch  52  being sized to receive the sprinkler head  30 . See  FIGS. 10 and 11 . The drain  17  is disposed in the bottom of the branch  52 . To encase the sprinkler head  30 , a user places the first shell  11  up against the bottom of the supply pipe  33 , closes the second shell  12  over the top of the supply pipe  33 , and latches the casing  10 . Again, preferably the valve in the nozzle  22  is open when the user closes and latches the casing  10  so that pressure does not immediately begin to build inside the casing  10  before the casing  10  can be fully latched. The guides  27  and hinging and latching mechanisms described in the first embodiment may be used for the second embodiment as well. 
     The second embodiment may also be used with a terminal sprinkler head  30  such as the sprinkler head  30  illustrated in  FIG. 13 . This is accomplished by sealing the opening in the second neck  42  with a plug  53 , as illustrated in  FIG. 12 . The plug  53  has a head  54  made of a material that is substantially rigid but has some elasticity. The elasticity allows the head  54  to be inserted through the second neck  42  into the interior space, forming a watertight seal over the opening in the second neck  42 . Alternatively, a third embodiment of the casing  10 , shown in  FIGS. 13 and 14 , may be used for such terminal sprinkler heads  30 . The third embodiment retains the branch  52  of the second embodiment but removes the second neck  42 , so that only the neck  40  fits around the supply pipe  33 . To encase the sprinkler head  30 , a user places the first shell  11  up against the bottom of the supply pipe  33 , closes the second shell  12  over the top of the supply pipe  33 , and latches the casing  10 . Again, preferably the valve in the nozzle  22  is open when the user closes and latches the casing  10  so that pressure does not immediately begin to build inside the casing  10  before the casing  10  can be fully latched. The guides  27  and hinging and latching mechanisms described in the first embodiment may be used for the third embodiment as well. 
     With the casing  10  in place, water flowing from the sprinkler head  30  fills the interior space until sufficient pressure builds within the casing  10  at the mouth of the sprinkler head  30  to stop the flow of water. If the air inside the casing  10  is allowed to be displaced, either through the non-airtight seal or through the nozzle  22 , the interior pressure needed to stop the flow of water is reached once the interior space has completely filled with water. If the seal is airtight and the nozzle  22  is closed, the total pressure, comprising air pressure and water pressure, will stop the flow. Once head has been encased, the remainder of the fire sprinkler system may operate normally. The sprinkler head  30  may then be bypassed or the system water may be shut off at an opportune time, after which the valve in the nozzle  22  may be opened for controlled emptying of the water in the casing  10  and the casing  10  may be unlatched and removed and the malfunctioning sprinkler head may be repaired. 
     While there has been illustrated and described what is at present considered to be the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made and equivalents may be substituted for elements thereof without departing from the true scope of the invention. Therefore, it is intended that this invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.