Descriptions of Patents Recently Issued of Interest to Fire Departments—New Fire Alarm—Fire Extinguishing Grenade
Fire Alarm Apparatus
A new design of fire alarm apparatus (patent No. 1,570,255) has been patented by Hugo Hunke of Taylor, Tex.
The illustration, which is partially in section, depicts the indicating and alarm mechanism at a fire station and shows the fire alarm circuit.
A circuit is provided from the source of electrical energy to and from the indicating mechanism and is connected with one of the circuit closing contacts or switch points of alarm boxes. This is arranged at the points to be protected. Other conductors which complete the circuit conductors, extend from the circuit closing contacts to the indicating mechanism at the central or fire station. In the illustration three of the fire alarm boxes are shown but any number of boxes may be used. Included in the system is an alarm circuit which obtains its energy from batteries or other sources and which is connected with a bell, siren or other audible signal which is actuated by one of the fire alarm box circuits.
At the station is a panel board upon which are mounted a series of indicating devices—a cover plate is provided for each indicator. A spring is provided for keeping the cover plates closed until released by the actuating mechanism.
A notch is provided at each end of the cover plate to receive a locking stud upon one end of a centrally pivoted latch whereby when the cover plate is in closed position and engaged by the latch, the plate will be held from opening by the action of the spring. The lower end of the latch forms a trip arm which engages with a striker on an armature which is normally held retracted by the spring and is adapted to be operated by an electro-magnet.
When the switch device of an alarm box is operated at a station to close the circuit, the magnate is energized and attracts the armature causing the striker to engage and release the latch and the cover plate will then fly upward under the action of the spring. The cover plate also forms a switch for closing the alarm circuit containing the alarm devices of the bell and siren; each cover plate is provided with circuit closing contacts or plugs.
The plugs are designed to engage spring sockets or jackets which are mounted on the shelf. A pair of sockets are provided for the cooperation with the switch contacts of each cover plate and each pair of sockets are independently connected. The siren and bell may be located at some remote point so that an alarm will ring within the engine house and also at some exterior place.