New Automatic Fire Extinguisher
A new automatic fire extingusher which will act under the influence of heat and flame has recently been invented. It is especially adapted for use on fire apparatus and other automobiles. In Fig. 1 of the illustrations a section of the device is shown ready for action. Fig. 2 is a similar view, after the keeper has been melted and the fuse projected, as in the flame area. Fig. 3 is a side elevation of the device as shown in Fig. 1. Fig. 4 is an end elevation of the same. Fig. 5 is a view in perspective on a reduced scale, showing the device mounted in a suitable holder.
Referring to the illustration, the container for the fire extinguishing powder comprises the cylinder 6. and the end pieces or caps 7 and 8. These elements may be made of paper fibre or similar material suitably coated to render them moisture proof. The end piece 7 is provided with the opening 9 for the introduction of the powder or other fire extinguishing material 10 into the receptacle. This opening 9 is then closed by the covering piece 11. glued or otherwise securely secured to the end piece 7. The end piece 8 is also provided with a central opening for receiving the flanged cylindrical member 12 having the flange 13 and the mortised recess 14. A cylinder or cartridge 15 is fitted into member 12 and projects centrally well into the body of the cylinder 6. The cartridge has at its innermost end a small charge of explosive, such for example gun powder, as at 16, secured in place between the plug 17 anti the closing gap 18. The plug 17 is provided with a channel 19 extending longitudinally entirely through the plug 17. A fuse 20 extends from the charge of the explosive 16 through the plug 17, and the balance of its extension is coiled or folded in the chamber 21 formed within cartridge 15 between the plug 17 and the outer end of the cartridge. A helical spring 22 is seated in the space 23 formed between the cartridge 15 and an offset portion of the member 12. The outer end of spring 22 is connected to the outer end of fuse 20. The spring 22 is normally maintained compressed hv a keeper 24. This keeper 24 is inserted through the notches 25 and then turned in the mortised opening 14 into the position as shown in Fig. 4. This keeper is made of a suitable material such as an alloy of metal having a fusing or melting point suitably high safely to resist a temperature considerably above the normal temperatures of the spaces in which the device is mounted but sufficiently low to melt when an abnormal temperature occurs in this space due to a fire.
When the device is suitably positioned on the car preferably near the engine and carbureter and beneath the hood, it may be carried without injury as long as normal conditions are maintained. When however a fire occurs in this space the keeper 24 is melted, the spring 22 is released and the fuse 20 is extended by the spring, across a very extended area affected by the flame. Obviously the fuse coming into contact with the flame, becomes ignited and burns until it has ignited the explosive charge 16. This results in an explosion which causes a bursting of the cylinder 6 and an effective distribution of the extinguishing substance 10, throughout the flaming area and thus smothers and extinguishes the fire. In order to assure an even disintegration of the cylinder 6, it is best to provide the cylinder walls with a plurality of evenly disposed staggered slits 29 as shown in Fig. 2. A thin strip or coating of impervious material is applied to the inner or outer wall of the cylinder, to prevent the passage of the material or of air or moisture through the slits 29.
The device may be placed in any desired space where a fire may occur and it may he so positioned, with respect to the direction of its axis as to project the fuse in the direction in which the hottest or first flame is likely to occur, or two or more such devices may he placed to be affected by a flame in a given area and to project their fuses in different directions. The charge of explosive necessary to burst the container and distribute the extinguishing substance over the required area, need be very small, and therefore there is no danger whatever attending such explosion.
All of the elements except the keeper and bracket may be made of paper and other fibrous substances and at very small expense.
The extinguisher is the invention of Reno De Orveille Johnson, of Palmyra, N. J., whose application was filed Oct. 29, 1921, under serial No. 511,47. Mr. Johnson has assigned one-quarter of his invention to Joseph G. Seel and onequarter to Alvan E. Swain, both of Palmyra. The patent was granted April 8, 1924 and the number is 1,489,703.