no claim of novelty is asserted for the sprinkler heads served by the present device but their construction and mode of operation are relevant to this invention and , therefore , they are discussed briefly hereinbelow . pendent - type : in fig1 - 7 there is shown a pendent - type sprinkler head 10 equipped with a threaded conduit 11 for conveying fluid from an overhead water supply ( not shown ) through a fluid - emitting orifice 12 , suspended beneath the sprinkler head housing 13 on a pair of guide rods one of which is shown as 14 in fig1 and 2 is a circular baffle plate 15 and a valve assembly 16 . said baffle plate receives the fluid emitted from orifice 12 and disperses the stream in a generally uniform pattern in finely divided form . in fig1 - 3 said guide rods are shown in a lowered position with the baffle plate 15 and valve assembly 16 in an activated or discharge mode , that is , positioned to receive the stream which flows from orifice 12 , whereas , fig4 - 7 show the guide rods in a raised position with the baffle plate and valve assembly in a non - discharge mode . the baffle plate 15 is serrated to distribute the stream evenly in all directions and there is secured to its topside a flat circular disc 17 upon which there is disposed a tacky film 18 for contacting the orifice 12 and obturating fluid flow when the baffle plate 15 and valve assembly 16 are in a non - discharge mode . the shut - off device for the pendent sprinkler head 10 is shown generally as 22 in fig1 - 7 . this device consists essentially of a hollow cylindrical body equipped at the bottom end with a hexagonal opening and at the top or opposing end with a contoured opening 24 and a cavity 27 for receiving the flange 19 of said sprinkler head and the sprinkler head housing 13 . the cavity sidewalls 31 extend downwardly for about half the length of said body and terminate in a flat base 25 which extends laterally to provide the circular space or cirque shown as 34 in fig2 and 6 . centrally disposed within said cavity is a circular projection 29 which extends upwardly from the base 25 to provide a support means for a flat circular seat identified as 26 in fig2 and 6 . the seat 26 is a tubular member fitted onto an accommodating segment of projection 29 for receiving baffle plate 15 and spherical segment 30 ( fig2 ) when the shutoff device 22 is impressed onto an activated sprinkler head 10 . the sidewalls 31 of the cavity 27 include opposing apertures in the form of horizontally disposed channel members 32 and 33 . when viewed externally these channel members may appear identical but a careful examination reveals that they lie on a bias to the extent shown in fig2 and this obliquity provides means for frictionally engaging the projection members 20 and 21 of flange 19 . when the shut - off device 22 is impressed onto an activated sprinkler head 10 and rotated in a clockwise manner . included in the sidewalls 31 of said cavity is a horizontally disposed pattern of vent holes . an activated sprinkler head 10 emits a liquid stream under some considerable pressure and the present invention allows an installer to abate this difficulty by providing within said sidewalls a plurality of apertures through which water can be diverted and released as the device is being installed . operation : the sprinkler heads served by the present invention are equipped with temperature - responsive films which retain the shut - off valve within the fluid - emitting orifice by adhesive means ; however , any exposure to incendiary temperatures , that is , temperatures in excess of about 105 ° c . will cause the adhesive to melt so that water pressure within the conduit 11 can expel the valve assembly and permit fluid to be discharged from orifice 12 . the fluid thus emitted comes into contact with the baffle plate 15 and directs the liquid stream evenly to adjacent areas in the form of a finely divided spray . the present device obturates fluid flow by returning the valve assembly 16 to the fluid - emitting orifice ( fig4 ). this shut - off stage is achieved by positioning the shut - off device 22 beneath the activated sprinkler head 10 in such manner that the cutout segments 35 and 36 are in registry with projection members 20 and 21 of flange 19 ( fig1 and 2 ). when registry is assured the device 22 is impressed upwardly onto the sprinkler head 10 as a result of which the tubular seat 26 contacts the underside of baffle plate 15 and brings the valve assembly 16 into shut - off engagement with the fluid - emitting orifice 12 ( fig4 and 5 ). locking is achieved by rotating the shut - off device 22 in a clockwise direction until projection members 20 and 21 are brought into frictional engagement with channel members 32 and 33 ( fig6 and 7 ). a sprinkler head 10 secured in this manner may be removed by simply rotating the shut - off device in a counterclockwise direction . alternatively , the shut - off device 22 may be left unattended without risk because it is fabricated from compositions which melt at incendiary temperatures . accordingly , any rise in temperature to critical levels , that is , temperatures in excess of about 105 ° c . will cause the shut - off device 22 to lose its hold and automatically return the sprinkler head to an activated mode . sidewall type : fig8 - 14 illustrate a shut - off device 52 for a sprinkler head of the sidewall type 40 . this sidewall sprinkler 40 is essentially identical in operation to the pendent - type sprinkler shown as 10 in fig1 - 7 except that the baffle plate 45 consists essentially of projecting fingers , guide rod 44 and a vertically disposed arcuate deflector 65 for directing water in a given direction . the shut - off device which serves this sidewall sprinkler head 40 is the hollow cylindrical body shown generally as 52 in fig8 - 14 . this device is characterized by a hexagonal orifice 53 at one end and includes at the opposite end a contoured circular orifice 54 for receiving the projecting members 50 and 51 of flange 49 . extending downwardly from orifice 54 is a cavity 57 defined by downwardly extending sidewalls 61 and the flat laterally extending base shown as 55 in fig9 and 13 . centrally disposed within said cavity and extending upwardly from the base 55 is a circular projection 59 which terminates in a flat support upon which there is secured the tubular seat identified as 56 in fig9 - 11 and 13 . the upwardly projecting member 59 is centrally disposed within the cavity 57 so that its sidewalls and the cavity sidewalls 61 combine to form a circular space or cirque 64 for receiving the deflector 67 of the sprinkler head 40 when the shut - off device is impressed onto an activated sprinkler head . included within the sidewalls of cavity 57 are apertures in the form of horizontally disposed channel members 62 and 63 which extend through the walls of the shut - off device 52 . these channel members are obliquely biased to provide means for frictionally engaging the projection members 50 and 51 of flange 49 when the shut - off device 52 is impressed onto an activated sprinkler head 40 and rotated in a clockwise direction . in fig9 only the obliquity of channel member 62 can be seen in the drawings but channel member 63 is identically disposed . operation : the shut - off device 52 is installed by aligning its cutout segments 65 and 66 with the projection members 51 and 51 of the sprinkler head flange 49 and impressing the former upwardly with a thrusting force greater than the pressure exerted by the liquid stream emitted from orifice 42 . the plurality of holes within the sidewalls of the device 52 provide a form of pressure release by allowing water entrapped within the cavity 57 to escape and thus facilitate the installation procedure . the upward thrust of the shut - off device 52 onto the sprinkler head 40 brings the underside of baffle plate 45 into engagement with tubular seat 56 and causes the valve assembly 46 and film 48 to engage the fluid emitting orifice 52 where it creates a seal against further fluid discharge . at this juncture the projection members 50 and 51 are in view and can be clearly seen through channel members 62 . once the shut - off device has been installed and the flow of liquid has been stanched the sprinkler head 40 is secured against inadvertent discharge by turning said device in a clockwise direction so as to bring projection members 50 and 51 of flange 49 into engagement with the biased segment of the channel members 62 and 63 ( fig1 and 14 ). a sprinkler head secured in this manner can be reactivated by rotating the shut - off device 52 in a counterclockwise direction and withdrawing same in a downward fashion . alternatively , the shut - off device 52 can be allowed to remain on the sprinkler head without jeopardy because the device is fabricated from thermoplastic compositions which melt at sprinkler activating temperatures so that in case of a fire emergency the shut - off device 52 will simply melt , separate and return the sprinkler head to an operable mode . this invention has been described by reference to precise embodiments but it will be appreciated by those skilled in the art that this invention is subject to various modifications and to the extent that those modifications would be obvious to one of ordinary skill they are considered as being within the scope of the appended claims .
a device for terminating the flow of fire - extinguishing fluid from an activated sprinkler head of the pendent and sidewall types . a cavity within the device receives the sprinkler head and a protuberance within said cavity engages the valve assembly and returns the shut - off valve to the fluid - emitting conduit . biased apertures within the sidewalls engage the sprinkler head flange and provide a locking means . the device is constructed from thermoplastic resins which melt and allow the device to become reactivated when ambient temperatures reach critical levels .