Abstract: Pressure relief valve including an annular nut of relatively high thermal conductivity including a first end portion providing an inwardly extending axial cylindrical surface and an internal annular surface extending radially outwardly from the cylindrical surface and including an internally threaded second end portion, and a fusible disc including a cylindrical first end portion provided with frictional enhancement means in frictional engagement with the cylindrical surface to mount the fusible disc frictionally in the annular nut and including an annular second end portion engaging the annular surface to position the fusible disc in the annular nut.

Abstract: The movement and mixing of microdroplets through microchannels is described employing silicon-based microscale devices, comprising microdroplet transport channels, reaction regions, electrophoresis modules, and radiation detectors. The discrete droplets are differentially heated and propelled through etched channels. Electronic components are fabricated on the same substrate material, allowing sensors and controlling circuitry to be incorporated in the same device.

Abstract: An appliance end fitting for connecting a gas operated appliance to a pressurized gas cylinder includes a simplified interior valve that acts as both a thermal valve and an excess flow control valve. The end fitting has an elongated body formed in two telescoping sections, an inner section, and an outer section. An interior opening extends through both sections and includes an enlarged center portion. A floating valve member in the center portion is movable toward a valve seat at an outer end of the center section. A spring urges the valve member away from the valve seat but excessive gas flow moves the valve member toward the valve seat and restricts the valve. The two sections of the body are held in an extended axial position by a heat activated material, such as fusible solder, where the nipple opens the cylinder shutoff valve when the body is connected to the cylinder outlet.

Abstract: A one-shot, electro-pneumatic actuator apparatus for quickly supplying a pressurized fluid to an external device upon the actuation of an external control signal. The actuator includes a housing having a first portion for containing a quantity of pressurized fluid, a second portion having a reduced, cross-sectional area, and a third portion. The second portion includes a sealing element disposed therein for containing the pressurized fluid held in the first housing portion. A coil is wound around the second housing portion and receives a signal from an external control subsystem which causes the coil to heat the second housing portion, and thus the sealing element, to damage the sealing element. This enables the pressurized gas to escape through the second portion into the third portion of the housing and subsequently to the external device being controlled.

Abstract: A thermal-pressure relief device, which has an adapter (20) threaded into the wall of a pressure vessel. The adapter contains an orifice (22) therethrough in line with a recessed cavity (32) which includes a raised stem (34). A blow out member (30) rests on the stem and overlaps the orifice to obstruct communication with the fluid inside the vessel. The blow out member is attached within the cavity by brazing with a filler metal in the form of a temperature responsive amalgam (38), preferably a eutectic alloy. When ambient temperatures are elevated above the melting point of the amalgam the blow out member is released freeing the orifice relieving the pressure within the vessel preventing a sudden structural failure. Optionally a protective cover in the form of a cap (42) with an impact surface (40) contains the blow out member when it separates from the adapter and a number of vents (48) diffuse the fluid from the pressure vessel in a safe direction.

Abstract: A pressure relief device having a housing including an inlet, an outlet, and an inner wall defining a bore connecting the inlet and the outlet. The inlet is in communication with a fluid under pressure in a pressure vessel. The bore includes an inlet portion extending from the inlet toward the outlet, and an outlet portion extending from the outlet toward the inlet. The bore also includes a tapered portion connecting the inlet portion and the outlet portion. The inlet portion has a diameter which is less than the outlet portion's diameter. A plug is located in the bore and movable from a closed position, in which flow of fluid through the bore is blocked, to an open position, in which flow of the fluid through the bore is permitted in response to a pressure differential between the inlet and the outlet.

Abstract: The heat actuated drain shutoff provides rapid actuation to stop the flow of a burning liquid into a drain system in order to prevent further damage to the drain system and structure in case of fire. The present shutoff includes a fusible element which melts when subjected to sufficient heat, thereby releasing a spring loaded valve to shut off flow through the drain. The spring actuation enables the device to be installed in any orientation, and the device is also adaptable to any environment having a drain for collecting flammable grease and liquids, such as kitchen or restaurant ventilation systems, service station islands, automotive repair shops, etc., where flammable liquids collected in a reservoir may be ignited.

Abstract: The present invention is to provide a thermally-sensitive safety device for gas tubing including a main body provided with an inlet, an outlet and a gas passage communicated with said inlet and said outlet, and a thermally-sensitive control valve mounted in the gas passage. The control valve has a ball, which is normally biased by a spring to stop against a thermally-sensitive member, and a bushing with through hole in alignment with the ball. The thermally-sensitive member melts while ambient temperature is higher than the melting point thereof, whereby said ball is biased by said spring to contact against and seal the through hole of the bushing such that the gas passage is blocked off.

Abstract: The valve is intended to be opened at a predetermined temperature in order to release the pressurized fluid from the tank and its opening is triggered by melting of a meltable material. It comprises a body in the shape of a socket (10), the open end of which is exposed to the gas pressure and the bottom of which is closed except for a minuscule orifice (12). The side wall of the body (10) comprises at least one radial opening (14) and the body (10) is engaged, by its bottom, by sliding, in a cap (16) of complementary shape and is fastened thereto by means of the meltable material (18). The cap (16) comprises at least one access (20) to the atmosphere and, after melting of the meltable material (18), can be moved with respect to the body (10) until each access (20) communicates with a side opening (14) in the body (10).

Abstract: A relief device for a high-pressure gas container, comprising a main body having a generally uniform outer circumference and that defines a primary bore, the primary bore in fluid communication with an interior volume of the high-pressure gas container, the main body having a secondary bore, the secondary bore located within the outer circumference and in fluid communication with the primary bore, a spud assembly seated in the secondary bore, the spud assembly including a rupture disc that relieves to the atmosphere the contents of the container when the container reaches a certain pressure, the rupture disc located within the secondary bore and within the outer circumference, the spud assembly and rupture disc fixedly attached.

Abstract: A housing (16) comprises a first housing (17) and a second housing (18). The first housing (17) is fixed to a gas cylinder (1) and is provided with a cylinder main valve (3) which is manually opened and closed. The second housing (18) is provided with a main stop valve (4) of an electromagnetically opening and closing valve. The second housing (18) is removably fixed to the first housing (17) by a tightening bolt (39). In this state where the second housing (18) is fixed to the first housing (17), the cylinder main valve (3) has a first valve chamber (44) communicated with a second valve chamber (63) of the main stop valve (4).

Abstract: A pressure relief device having a housing including an inlet, an outlet, and an inner wall defining a bore connecting the inlet and the outlet. The inlet is in communication with a fluid under pressure in a pressure vessel. The bore includes an inlet portion extending from the inlet toward the outlet, and an outlet portion extending from the outlet toward the inlet. The bore also includes a tapered portion connecting the inlet portion and the outlet portion. The inlet portion has a diameter which is less than the outlet portion's diameter. A plug is located in the bore and movable from a closed position, in which flow of fluid through the bore is blocked, to an open position, in which flow of the fluid through the bore is permitted in response to a pressure differential between the inlet and the outlet.

Abstract: A fire prevention safety device for a gas meter (3) has closure means (4, 4′, V) that can be activated by heat to interrupt the gas supply into the gas meter (3) in the event of a fire. The gas meter (3) is arranged in a bypass (2) of a gas pipe (1). At least one of the aforementioned closure means (4, 4′, V) for interrupting the gas supply is in each case arranged in the bypass (2) in the flow direction upstream and downstream of a sensor (31) belonging to the gas meter (3). The device permits a cost-efficient, simple and effective fire prevention safeguard, in particular for electronic gas meters.

Abstract: A bypass valve assembly, comprising: (a) a housing 12 having an inlet 16 and an outlet 18; (b) a valve member 20 disposed within the housing and being movable between a closed position and an open position; and (c) a slug of material 30 disposed in an initial substantially solid phase in contact with the valve member 20 so as to maintain the valve member in the closed position. The slug of material 30 is subsequently heatable into a substantially softened phase so as to permit the valve member 20 to move into the open position.

Abstract: A canister such as may be used for storing metal hydride. The canister includes a thermal fuse designed to relieve pressure in the canister when the temperature of the canister exceeds a threshold, for example, as a result of fire or direct heating. In addition, a latching assembly provides a quick-release connection for securely and reliably attaching the canister to a fuel delivery system, such as an input manifold for a fuel cell.

Abstract: A venting system for a tank in the form of a vapor bypass tube which is interfaced with a melt plug such that the bypass tube provides vapor pressure bypass of the melt plug hole. The vapor bypass tube has a first end mounted to the tank body circumscribably in relation to the melt plug. The vapor bypass tube has a second end, opposite the first end, which is open and located deep inside the tank. A vent aperture is provided in the vapor bypass tube adjacent the first end which provides vapor displacement from within the vapor bypass tube when the tank is being refueled.

Abstract: This invention relates generally to remotely operated well borehole or sub-sea tools for oilfield use, and more particularly, for a one shot valve useful for activating such well tools or sub-sea devices in a safe and reliable manner.

Abstract: A housing (16) comprises a first housing (17) and a second housing (18). The first housing (17) is fixed to a gas cylinder (1) and is provided with a cylinder main valve (3) which is manually opened and closed. The second housing (18) is provided with a main stop valve (4) of an electromagnetically opening and closing valve. The second housing (18) is removably fixed to the first housing (17) by a tightening bolt (39). In this state where the second housing (18) is fixed to the first housing (17), the cylinder main valve (3) has a first valve chamber (44) communicated with a second valve chamber (63) of the main stop valve (4).

Abstract: A safety valve for a compressed gas tank in which the plug is made of meltable material and intended to melt at a pre-determined temperature in order to release the compressed gas from the tank. The safety valve is essentially characterized in that the meltable plug is subjected to the action of a differential action sliding piston intended for reducing at least some of the effect of the gas pressure on the meltable plug.

Abstract: This invention provides methods and apparatus for performing microanalytic and microsynthetic analyses and procedures. Specifically, the invention provides a microsystem platform for use with a micromanipulation device to manipulate the platform by rotation, thereby utilizing the centripetal force resulting from rotation of the platform to motivate fluid movement through microchannels embedded in the microplatform. The microsystem platforms of the invention are also provided having microfluidics components, resistive heating elements, temperature sensing elements, mixing structures, capillary and sacrificial valves, and methods for using these microsystems platforms for performing biological, enzymatic, immunological and chemical assays. An electronic spindle designed rotor capable of transferring electrical signals to and from the microsystem platforms of the invention is also provided.

Abstract: The invention relates to a safety device for a sanitary hot water faucet characterized in that it comprises: a receptacle (10) passing all the way through a casing having a T shape, a seat (14) of a valve (15), delimited in the bore near its upstream end, installed in the receptacle from the upstream end: a valve (15) with an elastic element (16) that stresses it toward its so-called closed position and a so-called control rod (17) of the valve, locally comprising a fusible material (19) which, when it is subjected to a temperature higher than a predetermined temperature, melts so that the length of the control rod is reduced, thus causing the closing of the valve.

Abstract: A mechanical dual temperature damper closing mechanism having a primary link that separates when the ambient temperature reaches approximately 74° F., closing the damper. The new mechanism provides a reliable means for reopening the damper to allow airflow for the control of smoke spread. A secondary link is engaged within the new mechanism to reopen the damper. When the ambient temperature reaches 180° F. the secondary link separates, closes the damper such that it cannot be reopened.

Abstract: A fail-safe HVAC damper apparatus comprises a duct channel with a closure comprising one or more quadri-panel hinged elements, each with four panels connected by four parallel hinge pins. A gear shaft with a toothed gear is controllably rotated to linearly drive a spring-biased plate to move one of the hinge pins of each quadri-panel element between an open and a closed position. A drive motor may be activated to open or close the closure, e.g. by a smoke detector or other controller. A meltable fuse in the duct channel may be connected to a disconnect which uncouples the gear shaft and toothed gear, and a spring moves the closure to a default closed or open position.

Abstract: A deluge fire sprinkler system for suppressing fires occurring in an air environment, the air having an atmospheric pressure, the deluge fire sprinkler system including a network of water pipes having an interior volume, a water input port opening the interior space, and a plurality of water outlet ports further opening the interior space, the network of water pipes having an internal fluid at a pressure reduced below that of the outside atmosphere; a plurality of blow off caps for resisting aspiration of air into the water outlet ports and for permitting emission of water flowing under pressure from the water outlet ports, the blow off caps covering the water outlet ports, the blow off caps being adapted to permit air to aspirate into the interior space of the water pipe network upon exposure of such network to heat; a valve actuatable by a pressure rise, such valve operatively connected to the water input port; a pump for lowering the internal fluid pressure of the network of water pipes below that of the a

Abstract: A fire transmission prevention system (10) for use in a drainage system (100) to prevent the transmission of smoke and fire through the drainage system. The system is intended to be used in drainage systems in multi-story structures. The system includes a firestop (16), couplings (14, 26 and 30) and an air vent (42). The firestop prevents fire and smoke from moving through the inner passageways (44D) of the pipes (12, 24, 28 and 72) of a drainage system by blocking the inner passageway of the pipes with a fire resistant plug (20). The couplings are mounted in the floor (102) of the structure and are constructed and secured in the floor such as to prevent fire and smoke from passing around the couplings between the couplings and the floor. The air vent is provided in a vent pipe (40) of the system above a trap (38 or 78) of the system.

Abstract: A cap for venting a tank containing a fluid which expands in response to heat applied externally to the tank and which cap includes an outer annular nut, an inner circular central disc, and an intermediate annular ring of polymer-based material which softens in response to the externally applied heat to permit the inner circular central disc to be blown out of the outer annular nut thereby venting the tank and preventing the tank from exploding.

Abstract: A novel PRD (pressure relief device) design called fuse plug which is creep-resistant and leakage-free is developed to improve the thermal response of PRD to fire when it is used as a temperature safety device for valves, cylinders, pressurized pipes, or any pressure vessels, the new design being the combination of geometrical configuration of PRD structure and composite technology wherein the low-melting matrix alloy is dispersed with strong/stiff reinforcing agents such as cut-wire type aggregates/cylinders and such composite alloy is contained in a threaded/rugged cavity with the length/diameter ratio being greater than a minimum. The new design employs a disc-type seal T backed by the composite alloy, thus allowing the use of this new design for cylinders of poor thermal conductivity.

Abstract: The invention concerns a thermal safety fitting in which the closure motion of the obturator is longitudinal with respect to the obturator seat. The aim is to avoid lateral excursions of the obturator, while keeping manufacturing costs and structural size as low as possible. The obturator (12) is held in the open position in the housing (1) on the longitudinal axis of the obturator seat (28) by means of a generally U-shaped element (30). The two arms (9) of the U-shaped element (30) are located in the vicinity of a reduced-diameter section (17) of the obturator (12). The part (13) of the U-shaped element (30) joining the two arms (9) rests against a thermosolder (14). If the thermosolder (14) melts, the arms (9) no longer remain in the reduced-diameter section (17) owing to the change in the position of the U-shaped element (30), and the obturator (12) thus moves into the closed position under the action of a closing spring (24).

Abstract: A pressure relief device which operates between a closed condition wherein a fluid is contained within a vessel and an open condition wherein the fluid is discharged from the vessel by flowing through the pressure relief device. A plug is mounted within a cavity of a plug housing which is secured with respect to the vessel. The plug housing and/or the plug form at least one passageway. In the open condition of the pressure relief device, the passage allows communication between an inlet and an outlet of the plug housing. In the closed condition of the pressure relief device, there is no communication through the passageway and thus the fluid does not flow from the inlet to the outlet of the plug housing. A void, preferably an annular space, is formed between the plug and the plug housing. A fusible alloy, or other suitable eutectic material, is at least partially filled within the void.

Abstract: A self-extinguishing conduit for conveying a gas capable of supporting combustion of the conduit interior from an upstream to a downstream location includes a combustible tubing and a flow occluder operatively associated with the combustible tubing. The flow occluder is actuated by the heat of combustion within the combustible tubing to substantially halt the flow of gas through the combustible tubing. A combustion resistant material defines a select length of the conduit interior and is provided in series with the combustible tubing. The flow occluder is located downstream and proximate the combustion resistant material. A method for extinguishing combustion within a combustible conduit carrying a combustion supporting gas includes halting migration of combustion within the conduit at a select location and occluding the conduit at the select location.

Abstract: A thermally responsive pressure relief system is provided for a receptacle such as a pressure vessel. The system includes a thermally responsive pressure relief device on the vessel at a given location in communication with the interior of the vessel for venting the vessel in response to the pressure relief device being subjected to a given excess temperature. A heat pipe has one end thermally coupled to the pressure relief device and extends therefrom to a location remote from the given location. The heat pipe rapidly transmits heat from the remote location to the pressure relief device for venting the vessel in response to an excess temperature at the remote location.

Abstract: A pressure relief device that is normally closed and that moves into an open condition under certain design parameters which require fluid to flow from a relatively high-pressure chamber within a vessel to a relatively low-pressure atmosphere surrounding the pressure relief device. A plug housing has a throughbore which forms communication between the chamber within the vessel and the outside atmosphere. A plug is positioned within the throughbore. A fusible alloy at least partially fills a void or a passageway which is preferably formed between the plug and the plug housing. In an upset condition, such as an external fire, the temperature of the fusible alloy rises and thereby softens or melts the fusible alloy. As the fusible alloy softens, the bonding and shear strengths of the fusible alloy are reduced. The relatively high-pressure fluid acting upon the plug preferably forces or blows at least a portion of the plug out of the throughbore.

Abstract: A thermal-pressure relief device, which has an adapter (20) threaded into the wall of a pressure vessel. The adapter contains an orifice (22) therethrough with a blowout disc (30) overlapping the orifice to obstruct communication with fluid inside the vessel. The disc is attached by brazing with a filler metal in the form of a temperature responsive amalgam (38), preferably a eutectic alloy. When ambient temperatures are elevated above the melting point of the amalgam, the disc is blown out, freeing the orifice, relieving the pressure within the vessel, preventing an explosion. A protective cover in the form of a cap (42) with an impact surface (40) contains the disc when it separates from the adapter and a number of vents (48) diffuse the fluid from the pressure vessel in a safe direction.

Abstract: A thermal relief valve for a gas cylinder has a body with an inner wall defining a passageway for flow of fluid between inlet and outlet. A piston within the bore moves between a first position arresting flow from inlet to outlet, and a second position permitting flow from inlet to outlet. A restricting assembly for arresting movement of the piston towards the second position includes a thermal sensitive element of suitable eutectic material at the bore inner wall, with protrusions defining a first camming surface, and two or more restricting elements defining a second camming surface positioned to engage the first camming surface.

Abstract: In a valve for opening and closing a fluid path by rotating a plug in a sleeve made of teflon resin, a plug body and valve stem are connected together. The plug is pressed by a spring to form a seal so that a rotating and opening/closing operation of the plug is smooth. The plug is made in a shape of top cut conical form, wherein contacting protrusions which are formed at both ends of a fluid path are positioned within valve chamber to contact the plug. When a valve sheet of teflon resin is burned by fire, the plug is urged downward so as to closely contact the surfaces of the contacting protrusions so that fluid does not leak around the plug.

Abstract: The actuation of autoignition material in an airbag inflation device is facilitated by providing ports in the module can or housing of the airbag inflation device, and filling the ports with plugs of a fusible, low-melting material, so that when exposed to bonfire conditions, the plugs melt and the ports provide access to the autoignition material.

Abstract: Fiberglass reinforced plastic fume exhaust systems include duct walls having apertures therein covered with meltable thermoplastic resins mounted thereon which melt and open up the apertures when exposed to high temperatures thereby admitting ambient air therein to reduce the temperature downstream of the systems and reduce the suction pressure at source of the high temperatures.

Abstract: A hybrid gas generator includes a pyrotechnic gas generator joined to a high-pressure vessel which is sealed with a sealing disk composed of a substance which chemically reacts with propellant gas produced in use so that the sealing disk is opened with an advantageously reduced acoustic pressure. The propellant gas is chemically reactive and is produced from a propellant composition which is present in a surplus amount and which is composed of a propellant which is oxidizable and at least one oxidant for oxidizing the propellant. The propellant gas attacks the sealing disk chemically and thermally, and continuously burns through it to release the gas from the high-pressure vessel into a mixing chamber in the pyrotechnic gas generator.

Abstract: A bidirectional solenoid operated valve for controlling the flow of a compressed gas to and from a pressurized vessel is provided which automatically blocks the flow of gas out of a cylinder to a gas line in the event of an electrical failure or crash and which will not fail catastrophically in the event of a crash. The bidirectional valve includes a manual lockdown feature, an integral electrical pass through assembly, and a thermally activatable pressure relief device.

Abstract: A thermally responsive pressure relief system is provided for a receptacle such a pressure vessel. A passage communicates the interior of the vessel with the exterior thereof. A closure member is positioned in the passage. A fusible bonding material of a selected melting point fixes the closure member in the passage. The closure member includes an integral rupturable section that ruptures at a selected pressure differential between the interior and the exterior of the vessel. The closure member may be mounted in a body member which, in turn, is mounted in an opening in the pressure vessel. The body member may be mounted on a valve which has the passage from the interior of the vessel communicating therethrough.

Abstract: A valve with a rotatable valving member has a vent hole extending between an internal cavity of the valve and another location to which excess pressure can be vented. The vent hole is sealed with a consumable vent hole seal device that ruptures or otherwise vents under the high temperature and/or pressure of a fire and prevents dangerous pressure buildup within the internal cavity of the valve.

Abstract: The present invention relates to a modular compressed natural gas fuel unit comprising generally a tank adapted to contain compressed natural gas and a fuel supply unit integrally attached to the main valve of the tank.

Abstract: A bidirectional solenoid operated valve for controlling the flow of a compressed gas to and from a pressurized vessel is provided which automatically blocks the flow of gas out of a cylinder to a gas line in the event of an electrical failure or crash and which will not fail catastrophically in the event of a crash. The bidirectional valve includes a manual lockdown feature, an integral electrical pass through assembly, and a thermally activatable pressure relief device.

Abstract: A thermally responsive pressure relief system is provided for a receptacle such as a pressure vessel. A passage communicates the interior of the vessel with the exterior thereof. A closure member is positioned in the passage. A fusible bonding material of a selected melting point fixes the closure member in the passage. The closure member includes an integral rupturable section that ruptures at a selected pressure differential between the interior and the exterior of the vessel.

Abstract: A unique design for improved creep strength with a leakage-free structure is presented for manufacture of creep-resistant pressure relief device (PRD) of valves or cylinders or any pressure vessels as a fire protection safety device, the new design being the combination of geometrical configuration of PRD body shell and composite technology wherein the relatively weak matrix phase is dispersed with strong reinforcing agent and such composite mixture of matrix phase/reinforcing agent is contained in a nonslip structure of PRD cavity with a length/diameter ration being greater than about one such that the external load is transferred to the PRD structural body via stress transfer mechanism through reinforcing agents. The PRD's or fuse plugs fabricated by techniques of the present invention exhibit pronounced creep strength and show no gas leakage under high pressure/elevated temperature conditions realized during fires.

Abstract: A device (110) for protecting a clutch (C) against overheating from externally caused problems such as rapid cycling is disclosed including a heat conductive plug (120) sealed in an escape port (116) of a fitting (112) by fuse material (124) such as lead. The fitting (112) is threadably, sealably received in a bore (104) formed in the friction interface disc (12) of the clutch (C). The bore (104) is in fluid communication with the cylinder (30) of the clutch (10) which slideably mounts a piston (10) connected to the friction interface disc (12). Fluid pressure introduced into the cylinder (30) by conventional conduits (42) moves the piston (10) therein against the bias of a spring (56) when fluid flow from the cylinder (30) through the bore (104) is blocked by the overheating protection device (110).

Abstract: An air bag device for use in a passenger's seat is formed of a retaining box having an opening disposed at the front face for expanding an air bag and air intake ports disposed on the lateral side for intaking air, seat-like valves disposed in the retaining box, the valves being capable of covering the lateral sides thereby closing the air intake ports and moving from the lateral side thereby opening the air intake ports, a gas generator disposed to the deep inside of the retaining box, and a lid for covering the opening of said retaining box. The valves are made of such a material as melting at a temperature lower than the igniting temperature of the gas generator.

Abstract: There is provided a novel dual functioning, dual metal safety release valve for a pressure cooker. This valve comprises a metallic retainer member having a bore therein in which is held a fusible metal alloy. The metallic retainer is held in a suspended manner loosely in an opening in the lid of the pressure cooker contrary to the conventional manner in which the said release valve is sealingly fitted to the pressure cooker. The safety release valve is held at a specific angle and is so fabricated that when the pressure cooker is in operation, the safety release valve remains in suspended condition in the opening of the lid of the cooker, thereby letting air to escape first and when substantially all the air has escaped, the developing steam pressure forces the safety release valve upwards and a sealing of the opening in the lid of the cooker is achieved.

Abstract: An apparatus arranged to orient a closure cap over an entrance opening of a chimney stack to prevent a fire from projecting through the stack with the apparatus to include a spring-biased member and a fusible link permitting release of a plug member to secure the plug member within the chimney stack upon release of the fusible link.

Abstract: A poppet valve structure has a valve plug biased inwardly to close a vent opening (10). A connector member (40, 58) includes a cage (40) extending inwardly from the valve plug and a separately formed bottom plate (58) secured to the cage (40). The plate (58) defines a radially outwardly opening recess (64) and a first pair of axially spaced apart confronting surfaces. A spring abutment member (66) surrounds the plate (58) and defines a radially inwardly opening recess (74) and a second pair of confronting surfaces. The two pairs of surfaces confront and substantially contact each other. The recesses (64, 74) together define a substantially closed annular chamber. The chamber may be formed by a pair of confronting channels (64, 74) or defined axially between two flanges (61, 67) on the plate (58') and the abutment member (66'), respectively. A ring of fusible material (76) is cast in situ within the chamber to interconnect the plate (58) and the abutment member ( 66).