Patent ID: 6105678
Filing Date: 2000-08-22
Classification: A62C

Abstract:
A heat-responsive fire extinguishing assembly for a ventilating duct which draws hazardous gas out of a work site, the ventilating duct having an inner wall, an outer wall opposite to the inner wall in a radial direction, and an insert hole extending radially from the outer wall to the inner wall, said fire extinguishing assembly comprising:a mounting seat including an inner seat wall adapted to be mounted on the outer wall so as to cover the insert hole, an outer seat wall having an inner peripheral seat to define a first through hole therein that extends to said inner seat wall, and an annular insert portion extending from said inner seat wall and in fluid communication with said first through hole, said annular insert portion being of such a dimension so as to be adapted to be inserted fittingly into the insert hole to establish fluid communication between an interior of the ventilating duct and said first through hole;an elongate fire extinguishing body includinga connecting end portion adapted to be in fluid communication with a fire extinguishing solution reservoir,a free end portion disposed to be in fluid communication with said connecting end portion and to be brought to pass through said annular insert portion and so as to be adapted to extend inwardly of the inner wall via the insert hole,a valve member disposed between said free end portion and said connecting end portion to control the fluid communication therebetween during on and off states,a nozzle head disposed in said free end portion for discharging the fire extinguishing solution when said valve member is in the on state, anda heat detecting sensor disposed in said free end portion and adapted to actuate said valve member to the on state when the heat detected thereby reaches a predetermined heat value;a protective cap member made of a heat fusible and gas impermeable material, and having a closed end portion with a periphery, and an annular end portion extending from said periphery in a longitudinal direction so as to form an annular edge distal to said closed end portion, said protective cap member being disposed to isolate hermetically said free end portion from the interior of the ventilating duct and further having a mounting flange integrally formed with and extending outwardly and transversely from said annular edge, said mounting flange being of a dimension to abut against said inner peripheral seat when said protective cap member is brought to cover said free end portion and is led to pass through said first through hole from said outer seat wall so as to be adapted to protrude inwardly of the inner wall;a clamping ring disposed to be sleeved movably on said fire extinguishing body so as to be brought to abut against said mounting flange; anda tightening member disposed to force said clamping ring to abut against said mounting flange, thereby tightly sandwiching said mounting flange between said clamping ring and said inner peripheral seat.