A fire extinguishing kit includes a self-contained wall or ceiling mountable fire-extinguishing device having a base plate with an upstanding igniter and a depending non-projectile thermal actuator. The base plate is surrounded by a hollow frangible hull which in turn is supported by another base plate which also supports from below a distal end portion of the depending non-projectile thermal actuator. The hollow frangible hull is loaded with a sufficient amount of a dispersible dry fire-fighting chemical agent to facilitate extinguishing a small-localized fire when dispersed by the isotropic explosive force of the igniter.
Referring now to the drawings and more particularly to 1-3 there is illustrated a fire extinguishing kit 10 and explosive device 110, which are constructed in accordance with a preferred embodiment of the present invention. As best seen in
Considering now the kit 10 in greater detail with reference to
Considering now the fire-extinguishing device 110 in greater detail with reference to
The fire-extinguishing device 110, further includes another base plate or external bracket 118, which supports from below a distal end portion 117 of the depending non-projectile thermal actuator 116 as well as a hollow frangible hull 120 that surrounds the internal bracket 112. The external bracket 118, as best seen in
Considering now the fire extinguishing device 110 in still greater detail, the fire extinguishing device 110 generally includes four major components: (a) a containment vessel or hull 120 composed of a plastic foam material such as polystyrene foam or expanded polystyrene foam; (b) an igniter 114 carrying an explosive charge 712 (in combination sometimes called an explosive device 114); (c) a dry powder type of fire extinguishing material 150, such as ammonium phosphate or sodium carbonate surrounding the explosive device 114 and confined within the containment vessel 120 by the explosive shield 112 which supports from below both the explosive device 114 and the fire extinguishing material 150; and (d) an external bracket 118, which supports from below: a) the internal bracket 112; b) the thermally sensitive actuator 116 depending from the explosive shield 112 , and c) the containment vessel 120. This unique arrangement of the brackets 112 and 118 in combination with the explosive device 114, thermally sensitive actuator 116, and low density, rigid plastic containment vessel 120, which is loaded with the fire extinguishing material 150, provides a highly efficient and extremely safe fire extinguishing capability. More particularly, upon denotation of the explosive device 114, the fire-extinguishing device 110 will fragment into a plurality of low-density fragments, which are substantially harmless to a human in close proximity thereto. Moreover, the explosive device 110 is also harmless to the auditory system of a human in close proximity to the device 110 when the explosive device 114 detonates.
It should be noted that in the above-described arrangement, it is important that the outer hull 120 have a uniform thickness throughout to ensure that there is an equal dispersion of the pressure forces to cause the fire retardant material 150 to spread out in a generally spherical pattern in response to the explosive force generated by the explosive device 114. In addition to the thickness and density of the hull structure 120, it should be noted that the polystyrene foam material itself affects the spread pattern of the chemical agent 150. That is, if the structural material of the hull 120 were very dense and thick, the explosive charge of the igniter 114 would cause the hull to violently explode which would degrade the structural integrity of the hull 120. However, if the hull is composed of a low-density rigid plastic or foam material, which is thin and uniform, the hull 120 will explode and fragment only with a sufficient force to cause the fire retardant agent 150 to be dispersed in a circular pattern over a localized area. In short then, the density of the foam material is not so important as the density of the foam coupled with the thickness of the hull wall. In this regard, it has been found that a density of less that one-pound per cubic foot is preferred which results in a thickness of about 0.375 inches.
It should also be understood that the isotropic distribution of the explosive force generated by the explosive device 114 helps to reduce the resultant forces on the central actuator structure 116. That is, in case of the hull 120, which has a sphere or ball-like structure, the explosive charge of the device 114 is placed at about a location, which is coincident with the geometric center of the spherical geometry of the hull 120. In this regard, when the device 114 explodes, a nearly isotropic distribution of pressure radiates from the center of the charge since this source point is strategically located at about the geometric center of the hull 120. Because of this radiating distribution of pressure, and the separation between the charge 712 and the internal bracket 112, only a small resultant force of energy is directed at the internal bracket 112, thus, greatly reducing the likelihood of any projectiles and any type of structural failure of external bracket 118.
From the foregoing, it should be understood by those skilled in the art, that the non-projectile producing actuator is created by the structural arrangement of the various component parts of the device 110, which are tied into the mounting brackets 112 and 118 respectively. Whether the explosive force is equal/isotropic or non-isotropic, the design of the preferred embodiment of the present invention will not produce any projectile as long as the resultant force of the device 114 when it explodes is less than the structural failure rating of the structure brackets 112 and 118 respectively.
Considering now the igniter 114 in greater detail with reference to
The device 114 of the fire-extinguishing device 110 is unique because it is a temperature sensitive trigger mechanism, which is housed within a self-contained unit that does not require an external power source. In this regard, the low cost components of the fire-extinguishing unit 110 are combined in a unique and novel manner. The temperature sensitive switch 116 enables the unit 110 to monitor the ambient temperature without consuming any power as the switch 116 remains in an open position until triggered by a sufficient ambient temperature rise to cause the switch 116 to close, which in turn allows the electrical current to flow in the igniter circuit 212. The battery 216 remains passive until energy is requested through the tripping of the switch 116. The explosive charge 712 also remains idle until set off by the device 114. Once the explosive charge 712 is detonated by the igniter circuit 212, the fire extinguishing material 150 is dispersed in a controlled manner (uniform pressure distribution) to put out a small-localized fire.
As best seen in
Considering now the holder 210 in greater detail, the holder 210 has a generally rectangular box-like frame 612 as best seen in
Considering now the explosive charge 712 in greater detail with reference to
Considering now the hull construction 120 in greater detail with reference to
When the two half sections 122 and 124 are interconnected forming the hull 120, the igniter assembly 114, via the downwardly depending support 618, is positioned within the hull interior aligned within the hole H of the lower section 124. It should be noted that the bracket 112, from which the support 618 depends, is also configured to engage the interior wall of the hull 120 and acts as a further stop or floor for the accumulation of the fire retardant agent 150 which is introduced into the interior of the hull through the hole H disposed in the upper section 122 as will be explained hereinafter in greater detail.
Considering now the downwardly depending support 618 in greater detail with reference to
Considering now the upper section 122 of the hull 120 in still greater detail, as noted earlier, once the two sections 122 and 124 are interconnected and mounted to the external bracket 118, the dispersible fire extinguishing material 10 is introduced into the interior of the hull 120 via the hole H disposed in the upper section 122. As the material 150 is introduced within the hull 120, it fills the interior surrounding the device 114. After the hull 120 is completely full, a plug 812 (
Considering in still greater detail the igniter assembly 114, the igniter circuit 212 includes an igniter 218 having an upper mounting loop 218A and a pair of igniter legs 218 B and C respectively. A box like spacer 218D helps hold the legs 218B and C spaced apart from one another. The igniter 218 is an off-the-shelf item, manufactured by Estes Industries under part number 302301. The thermal switch 116, which forms part of the igniter circuit 212, is also an off-the-shelf item, manufactured by Uchiya under part number UP72, while the battery receptacle R is manufactured by Mouser Inc. under part number 121-0626/0.
While preferred embodiments of the present invention have been described in detail for purposes of illustration and the advantages of the details, variations have been set forth and are possible. For example, the device is shown with a pair of batteries as opposed to a single battery. In this regard, it is contemplated that a single battery could also be utilized to provide the necessary power for the device. In short then, variations are shown to illustrate the broader aspects of the present invention, so that further embodiments, modifications and variations are contemplated, all as determined by the spirit and scope of the appended claims.
There have been many different types and kinds of explosive fire extinguishing devices introduced in the prior art. For example, reference may be made to the following published documents: INVENTORDATE OF ISSUANCEUS PATENT NO. 228,621FolsomJun. 8, 1880 336,981BartlettMar. 2, 1886 338,604LuysterMar. 23, 1886 370,874JohnsonOct. 4, 1887 655,599BraunwalderAug. 7, 1900 798,623BartlettSep. 5, 1905 883,856BowmenApr. 7, 1908 964,299McCallJul. 12, 19101,297,172HughesMar. 11, 19192,073,416FinziMar. 9, 19372,074,648HaimannMar. 23, 19372,091,589FinziMay 4, 19352,665,768TalbotJan. 12, 19542,873,806BittnerFeb. 17, 19573,833,063WilliamsSep. 3, 19744,285,403PolandAug. 25, 19814,964,469SmithOct. 23, 19905,050,683SaylesSep. 24, 19915,224,550BraggJul. 6, 19935,518,075WilliamsMay 21, 19965,881,819Walters et al.Mar. 16, 19995,992,531MikulecNov. 30, 19996,012,531RyanJan. 11, 20006,318,473Bartley et al.Nov. 20, 20016,612,243Italiane et al.Sep. 2, 20036,796,382KaimartSep. 28, 2004GB PATENT NO. 438,558FinziNov. 19, 1935 440,012FinziDec. 18, 1935 With respect to these prior art documents, of particular interest are the following: G.B. 440,012 by Finzi describes a fire-extinguishing device having a frangible containment vessel with a generally spherical shape. The containment vessel is formed from a low-density frangible material and is filled with a fire extinguishing material that surrounds an explosive device. A temperature sensitive fuse, coupled to the explosive device, causes the explosive device to detonate when the fuse is exposed to an elevated temperature. When the explosive device detonates, it breaks the containment vessel and disperses the fire extinguishing material over a localized area. U.S. Pat. No. 883,856 by Bowman discloses a rectangular shaped fire extinguisher, which holds a fire retardant material that surrounds an explosive charge. The explosive charge extends from one end of the container to the other end of the container. A wick fuse extends out from one end of the fire extinguisher. U.S. Pat. No. 2,873,806 by Bittner teaches a cylindrically shaped fire extinguisher, that holds a centrally disposed explosive charge which is surrounded by a fire retardant material. A fuse extends from one end of the container into the center of the container for igniting the explosive charge. U.S. Pat. No. 5,881,819 by Walters et al. discloses a heat sensitive fuse coupled to an explosive charge, where the fuse extends through an opening for activation after the temperature in the area of the device reaches a given high level. U.S. Pat. No. 6,796,382 by Kaimart illustrates a spherical shaped fire extinguisher with a centrally disposed detonator, which contains an explosive charge. A fire retardant material surrounds the detonator. A fuse extends from the outer surface of the extinguisher to the detonator. While the above-mentioned prior art devices were satisfactory for some applications, there is, nevertheless, a need for a new and improved fire extinguishing kit and device, which is safe, effective and relatively inexpensive.