New Fire Alarm
A feature of a new fire alarm is the use of an explosive which when ignited in case of a fire detonates so that those in other parts of the building are notified. The invention is particularly well adapted for awakening sleeping persons, as in a fire at night, who might otherwise meet disaster should the fire increase to any extent.
A further object is to provide a fire alarm in which the explosive is disposed in a bellshaped container open at the time at one end. whereby the report from the explosion may be greatly amplified and the damage done by the concussion of the explosion reduced to a minimum. Small quantities of the explosive will suffice and furthermore damage such as might occur from a slight explosion would be of little significance in the event of a truly destructive fire.
The explosive employed and the fuse for igniting it is entirely encased in a moisture-proof case when the device is not in actual use, thereby keeping the explosive and fuse in a dry condition which is essential to the successful operation of the device.
In the illustration. Fig. 1 is a sectional view of an embodiment of the invention, and Fig. 2 is a sectional view of the mechanism illustrated in Fig. 1 with the fuse exposed as in the event of fire.
To obtain the complete benefit from the use of the improved fire alarm, it is considered best to fix the devices, there being several used for each building, some within the walls of the building, over the furnace, inner flues which might be the direct cause through leakage, of fire, and in any other places where spontaneous combustion might occur, or where combustible materials are stored or permitted to accumulate.
For example, it is assumed that one of the devices is suspended by means of the ring 6 within the wall of a home and that the occupants ot the house are on an upper floor asleep and that fire is started from an overheated furnace or the like, igniting the walls on the first floor. Immediately upon the rise of temperature, due to the presence of flames within the wall, the solder, by means of which the cap 10 is secured and supported by the mushroom-shaped portion of the shaft 5, will melt and the cap 10, by virtue of the weights 13, will drop, assuming the position shown in Fig. 2.
When the fuse 14 is burnt to a point within the chamber 3, the explosive 4 will become ignited and a loud report will result to awaken the occupants of the building and this warning may permit them to leave the building before destruction has become too great to prevent the exit and imperil life. If desired, a lining of fire-proof material, such as asbestos sheeting may be employed on the inner side of the casing 1. The purpose of this fireproof lining is to prevent the heating of the explosive prior to the time that the cap 10 was dislodged from its connection with the conical member 9. It will therefore be apparent that such lining should be principally in the upper portion of the casing.
When the cap 10 drops, the fuses 14 are straightened out and larger portions of the fuses are exposed below the lower end of the casing 1 It then remains for the fire to ignite the fuses 14 which will readily occur, since the fuses are constructed of a highly combustible and readily ignited material. These are provided with two explosion chambers and two fuses. This is to make sure of the effective operation of the device. If one of the fuses 14 does not ignite, the other mav be ignited and the same rule applies where more than two fuses are used which might be necessary when the device is of a larger caliber.
The fire alarm is the invention of Charles De Roos, Sioux City, la., whose application was filed May 21, 1923, the serial number being 640,518. The patent was granted on November 18, 1924, the number being 1,515,936.