US-12623104-B2 - Anechoic chamber fire protection system

US12623104B2US 12623104 B2US12623104 B2US 12623104B2US-12623104-B2

Abstract

A nozzle box unit forming a component of an anechoic chamber fire suppression system is provided. The nozzle box unit includes a pusher assembly that is configured to dislodge a piece of acoustic material positioned in front of the nozzle box so as to permit discharge of a fire suppressing material from a nozzle mounted inside the nozzle box unit into the anechoic chamber.

Inventors

Corry Giffin
Gene Hill
Devang Patel
Bradford T. Stilwell

Assignees

FIKE CORPORATION

Dates

Publication Date: 20260512
Application Date: 20221229

Claims (20)

1 . A nozzle box unit comprising: a nozzle box configured to hold a nozzle operable to deliver a fire suppressing material into an anechoic chamber, the nozzle box comprising wall structure defining a compartment inside of which the nozzle is located, and an open face that is configured to permit communication between the compartment and an anechoic chamber external to the nozzle box; and a selectively actuatable pusher assembly, the pusher assembly being shiftable between a retracted position and an extended position, the pusher assembly being configured to dislodge a piece of acoustic material mounted in front of the nozzle box open face upon shifting from the retracted position to the extended position thereby permitting discharge of the fire suppressing material from the nozzle into the anechoic chamber, wherein the nozzle box wall structure comprises top and bottom walls, a back wall opposite the open face, and a pair of sidewalls extending between the back wall and open face and interconnecting the top and bottom walls, wherein the top wall comprises an opening to accommodate mounting of a nozzle within the compartment.
2 . The nozzle box unit of claim 1 , wherein the nozzle box is tapered between the open face and the back wall.
3 . The nozzle box unit of claim 1 , wherein the nozzle box unit comprises a flange located around the open face and configured to attach the nozzle box unit to a wall defining the anechoic chamber.
4 . The nozzle box unit of claim 1 , wherein a distance between the opening and the open face is less than a distance between the opening and the back wall.
5 . The nozzle box unit of claim 1 , wherein a width of the open face is greater than a height of the open face.
6 . A nozzle box unit comprising: a nozzle box configured to hold a nozzle operable to deliver a fire suppressing material into an anechoic chamber, the nozzle box comprising wall structure defining a compartment inside of which the nozzle is located, and an open face that is configured to permit communication between the compartment and an anechoic chamber external to the nozzle box; and a selectively actuatable pusher assembly, the pusher assembly being shiftable between a retracted position and an extended position, the pusher assembly being configured to dislodge a piece of acoustic material mounted in front of the nozzle box open face upon shifting from the retracted position to the extended position thereby permitting discharge of the fire suppressing material from the nozzle into the anechoic chamber, wherein the pusher assembly comprises a cylinder inside of which is located a rod, the rod having a distal end configured to engage the piece of acoustic material.
7 . The nozzle box unit of claim 6 , wherein the distal end comprises a bumper having a diameter greater than that of the rod.
8 . The nozzle box unit of claim 6 , wherein the rod has a path of travel that is substantially perpendicular to the open face.
9 . The nozzle box unit of claim 6 , wherein the distal end is located flush with or behind the open face when the pusher assembly is in the retracted position.
10 . The nozzle box unit of claim 1 , wherein the pusher assembly is configured to be connected to a source of a pressurized fluid.
11 . The nozzle box unit of claim 10 , wherein the source of the pressurized fluid is a pressurized gas reservoir or a pressurized fire suppressing material reservoir.
12 . The nozzle box unit of claim 1 , wherein the pusher assembly is configured to contact the piece of acoustic material mounted in front of the nozzle box with a force of at least 80 lbf.
13 . The nozzle box unit of claim 1 , wherein the pusher assembly is mounted to the nozzle box.
14 . A fire suppression system for an anechoic chamber, the fire suppression system comprising: at least one nozzle box comprising wall structure defining a compartment, and an open face that is configured to permit communication between the compartment and the anechoic chamber; a nozzle located within the compartment that is fluidly connected to a source of a fire suppressing material, the nozzle being configured to discharge a stream of the fire suppressing material into the anechoic chamber; a selectively actuatable pusher assembly, the pusher assembly being shiftable between a retracted position and an extended position, the pusher assembly being operable to dislodge a piece of acoustic material mounted in front of the nozzle box open face within the anechoic chamber upon shifting from the retracted position to the extended position thereby permitting discharge of the fire suppressing material from the nozzle into the anechoic chamber, wherein the pusher assembly comprises a cylinder inside of which is located a rod, the rod having a distal end configured to engage the piece of acoustic material.
15 . The fire suppression system of claim 14 , wherein the nozzle is connected to a source of a fire suppressing material.
16 . The fire suppression system of claim 14 , wherein the pusher assembly is connected to a source of a pressurized fluid capable of supplying a motive force for shifting of the rod within the cylinder and to cause the distal end to contact the piece of acoustic material mounted in front of the nozzle box with a force of at least 80 lbf.
17 . A fire suppression system for an anechoic chamber, the fire suppression system comprising: at least one nozzle box comprising wall structure defining a compartment, and an open face that is configured to permit communication between the compartment and the anechoic chamber; a nozzle located within the compartment that is fluidly connected to a source of a fire suppressing material, the nozzle being configured to discharge a stream of the fire suppressing material into the anechoic chamber; a selectively actuatable pusher assembly, the pusher assembly being shiftable between a retracted position and an extended position, the pusher assembly being operable to dislodge a piece of acoustic material mounted in front of the nozzle box open face within the anechoic chamber upon shifting from the retracted position to the extended position thereby permitting discharge of the fire suppressing material from the nozzle into the anechoic chamber, wherein the fire suppression system further comprises a secondary pusher assembly that is laterally disposed from the at least one nozzle box, the secondary pusher assembly being configured to dislodge a second piece of acoustic material located adjacent to the piece of acoustic material dislodged by the pusher assembly associated with the at least one nozzle box.
18 . The fire suppression system of claim 14 , wherein the nozzle is configured to discharge the stream of the fire suppressing material in a spray pattern having an angular expanse of at least 30°.
19 . The fire suppression system of claim 14 , wherein the nozzle box wall structure comprises top and bottom walls, a back wall opposite the open face, and a pair of sidewalls extending between the back wall and open face and interconnecting the top and bottom walls.
20 . The fire suppression system of claim 19 , wherein a distance between the nozzle and the open face is less than a distance between the nozzle and the back wall.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS The present application claims the priority benefit of U.S. Provisional Patent Application Ser. No. 63/295,640, filed Dec. 31, 2021, entitled ANECHOIC CHAMBER FIRE PROTECTION SYSTEM, incorporated by reference in its entirety herein. BACKGROUND OF THE INVENTION Field of the Invention Embodiments of the present invention are directed towards apparatus used in the implementation of fire suppression systems for the protection of anechoic chambers. In one particular embodiment, a nozzle box unit is provided having a pusher assembly that is configured to dislodge a piece of acoustic material positioned in front of the nozzle box. Description of the Prior Art Anechoic chambers are rooms designed to absorb sound and electromagnetic waves from both interior and exterior sources. Often, anechoic chambers are isolated from waves entering from outside of the chamber. Within the chambers, tiles of acoustically absorbent or radiation absorbent material, depending upon the application for the room and usually in the form of pyramid-shaped cones, are installed on at least some of the wall, ceiling, and/or floor surfaces of the room. A person or detection equipment positioned within the room exclusively hears only direct sounds (or is exposed only to direct radiation), with there being no reverberant sounds or radiation. Thus, the anechoic chamber simulates an infinitely large room. Where fire protection of the chamber and its contents is required, gaseous clean agent fire suppression systems are commonly installed as the primary form of protection. There two main problems associated with the installation of a fire suppression system in an anechoic chamber. First, the piping associated with the system may produce undesirable reflections within the chamber. Second, any penetrations through the chamber walls may destroy the chamber's shield integrity and lead to entry of externally generated waves into the chamber. In addition, each penetration can act as an antenna, allowing signals generated within the chamber to be transmitted to the exterior of the chamber. In past fire suppression systems, mounting boxes containing nozzles connected to a source of a fire suppressing agent were installed entirely outside of the anechoic chamber walls. The mounting box was covered by an absorber cone that was frictionally held in place by surrounding cones. In the event of a fire, the fire suppressing agent would be delivered to the nozzle, and the spray emitted by the nozzle would dislodge the cone and permit the agent to be discharged freely into the chamber. System development assumed that a two-foot by two-foot cone would be directly centered in front of the mounting box. However, in reality, this was not always the case as the random placement of mounting boxes in the protected space often meant that parts of absorber cones ended up being patched together to sit in front of the mounting box. This scenario leads to different force requirements to dislodge these non-standard absorber cones. Thus, it could be very difficult to match the force required to dislodge the cones with the force of the agent dispensed through the nozzle. In order to ensure the cone is ejected, the contact surfaces of the cone and surrounding cones were often lined with a low-friction material, such as Formica™, to reduce the friction forces holding the cone in place, and thereby permit removal of the cone with lower applied force from the discharged agent. As is customary, fire suppression systems are generally tested periodically to ensure operational readiness. As a part of the testing of conventional systems, to ensure that the cone will be removed during discharge, each cone that is to be ejected must be tested with a force gauge to confirm that a minimum force of 29 lbf or less is required to remove the cone. This testing is tedious in that some anechoic chambers are very large in size, e.g., to accommodate an airplane, and require workers to position themselves high off the ground. In the past, the clean agents used for fire protection systems associated with anechoic chambers have been halocarbon compounds such as HFC-227ea or HFC-125 fire suppression agents. These agents are advantageous in that they are introduced into the chamber as a gas and are readily dispersed. However, the use of these compounds has become disfavored due to their perceived impact on climate change. The EPA has issued the AIM (American Innovation and Manufacturing) Act which reduces the amount HFC fire suppression agents that can be sold in the US. Thus, there is a desire to use more environmentally friendly suppressing agents, including fluorinated ketones such as FK-5-1-12. These fluorinated ketones have a drawback in that they can have much higher boiling points than traditional halocarbon compounds. Therefore, the fluorinated ketones may be discharged from the nozzles in liquid form and then evaporate post-discharge. The potential for dis