Fire sprinkler system and automatic shut-off valve therefor

In a fire sprinkler system for a protected building space, said system including a water distribution pipe extending across the top of the building space and fed from the building water main, at least one sprinkler head connected with said water distribution pipe, each said sprinkler head having therein a water exit passageway communicating with said water distribution pipe, a plug sealing said water exit passageway, and rigid fusible metal bar means anchored in said sprinkler head and bearing against said plug to restrain the same under normal circumstances against ejection from said exit passageway by the water pressure in said water distribution pipe;

• the improvement comprising:
• (a) a respective tubular pipe fitting associated with each sprinkler head and having opposite ends, each said pipe fitting being connected at one end to said water distribution pipe and at its other end to an associated sprinkler head, with the interior of each said pipe fitting being in communication with both said water distribution pipe and said water exit passageway in said associated sprinkler head;
• (b) a respective multi-vaned paddle wheel located interiorly of each said pipe fitting intermediate said ends thereof and having an axle mounted for rotation about an axis transverse to said pipe fitting;
• (c) a respective valve plate located interiorly of each said pipe fitting intermediate said one end thereof and the associated paddle wheel, each said valve plate having a valve opening therein disposed eccentrically to the associated axle and over the vanes at one side region of the associated paddle wheel;
• (d) a respective movable valve member located interiorly of each said pipe fitting and adapted to seal the associated valve opening, each said valve member being normally in a first position relative to the associated valve plate in which it leaves said valve opening thereof unobstructed and being arranged for movement to a second position relative to said associated valve plate in which it seals said valve opening thereof;
• (e) respective actuator means for each said valve member and operable for enabling movement of said valve member from said first to said second position thereof;
• and
• (f) respective gear means operatively interconnected between each said paddle wheel axle and the associated actuator means for operating the latter in response to rotation of said paddle wheel;
• (g) whereby, upon ejection of said plug from said water exit passageway of said at least one sprinkler head by the water pressure in said water distribution pipe in the event the temperature in the protected building space rises sufficiently to weaken said fusible metal bar means of that sprinkler head and cause the same to yield, the resultant rotation of the associated paddle wheel under the force of water flowing from said water distribution pipe into the respective pipe fitting and through said valve opening thereof past said associated paddle wheel and thence through said water exit passageway into said protected building space operates the associated actuator means via the respective gear means to enable said movement of the associated valve member over a predetermined time interval from said first to said second position thereof for interrupting, after said predetermined time interval, the flow of water into said protected building space.