Patent Application
20130186654
This application relates to a fire extinguishing system which is received in a space in a vehicle to extinguish fires and prevent explosions within the space.
Vehicles are often provided with fire extinguishing systems, and in particular with systems which are structured to quickly extinguish flames under any number of conditions. Often aircraft are provided with elaborate extinguishing systems that include long passageways to provide extinguishing materials from a distant source to any number of locations on the aircraft. Aircraft fire extinguishing systems may include a first dispensing cycle which is intended to extinguish a fire, and then an inert gas dispensing mode which occurs for a period of time, until the aircraft can land.
In general, the aircraft extinguishing systems are intended to control a fire until an aircraft can land. Thus, they are provided with long-term dispensing over many minutes, and even hours.
Ground based vehicles have typically been provided with less elaborate fire extinguishing systems. However, and in particular with ground based military vehicles, systems must be provided which are quickly actuated to extinguish a flame.
Thus, it is known to provide a cylinder in a vehicle space, such as a crew compartment, which has automatic fire extinguishing systems deployed after an event is detected. Typically, sensors identify a fire or explosion threat, and include a fast acting release mechanism and nozzle which enables rapid and efficient deployment of an agent throughout the crew compartment.
A fire extinguishing system for use in a crew compartment of a ground-based vehicle includes at least two cylinders. The cylinders dispense a fire extinguishing agent through a release mechanism. A control for the overall system is operable to actuate the two cylinders. A nozzle is positioned downstream of the release mechanism to dispense the extinguishing agent into the crew compartment. The majority of the dispensing from at least a first of the two cylinders occurs in less than five seconds.
These and other features of the invention would be better understood from the following specifications and drawings, the following of which is a brief description.
The dispensing can occur within 30 milliseconds of the detection occurring. The discharge can occur for 50 milliseconds to 1 second, as an example.
The agent will typically suppress or knock down the explosive threat. However, at times, it may be desirable or necessary to have the ability to react to a second event. As an example, and in particular with military vehicles, a crew compartment could be hit a subsequent time. Also, fuel leakage, etc., could re-establish a previously extinguished fire threat.
Thus, as shown in
A control 122 is set to actuate the fast acting release mechanism 123 as necessary. A sensor 121 provides signals to the control 122. The dispensing occurs very rapidly. This is true for all of the embodiments in this application. At least the initial cylinder has the majority of its dispensing occur in less than five seconds, and typically less than 1.5 seconds, and even more typically less than one second. The dispensing can occur much more rapidly, and can be on the order of 50 millisecond.
There may be a time delay between actuation of the cylinders 124 and 126, or the cylinder 126 may be kept in reserve for a subsequent restrike, or the flame restarting. As an example, a military crew compartment could be subject to multiple strikes, such as shells. Also, a flame that had previously been extinguished could increase in magnitude. The reserve cylinder may be actuated in those events. Both subsequent events may be sensed by the sensor 121.
In the
The
However, the control as utilized in the
Across all of the embodiments, it is expected and preferred that the nozzles 24 (or 206) be positioned to be within three meters of the cylinders. More preferably, the nozzle should be within one meter of these cylinders.
While some fire suppressant agents and inert materials have been disclosed above, any combination of agents and materials which are acceptable under current environmental regulations may be utilized. As an example, insert gases such as nitrogen or Argon, or CO2 up to 3 vol % may be used. Water-based agents may be in liquid and/or vapor form. Additives such as alkali salts (e.g., potassium bicarbonate, potassium acetate, potassium lactate, etc.) or foams (e.g., AFFF), and finally dry chemicals (e.g., sodium bicarbonate, potassium bicarbonate, Monnex™) may be utilized.
In addition, if a delay is desired between the actuation of the second cylinder and the first, the initiation time may be controlled. A fast electronic/pyrotechnic initiator can be utilized for the main cylinder, followed by a slower electronic or pyrotechnic initiator, or a gas generator which would take a longer period of time to actuate to initiate the secondary cylinder. Again, the amount of the delay would be controlled as desired. A difference in mass flow and discharge time can also be achieved between the two cylinders by varying the outlet diameter, and the volume of the cylinders, respectively.
In summary, the embodiments of this invention disclose systems where in a single system placed in a crew compartment is capable of multiple dispensing of fire extinguishing materials. A worker of ordinary skill in the art would recognize that modifications will come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 12151977.1 | Jan 2012 | EP | regional |
