Patent Application
20060139853
So-called electronic interface devices are used throughout communication networks to connect an external network with an internal network, for example.
Though these devices may be outdoors or indoors, regardless of their location, these devices, as well as other electronic devices, are subject to electrical surges due to lightning strikes.
In an attempt to absorb the energy created by a lightning strike, such devices may incorporate subcomponents that can protect the device from such large amounts of energy or can otherwise withstand such large amounts of energy. An example of such a subcomponent is a fuse.
Still, if a direct lightning strike or an unusually high-energy indirect lightning strike occurs, existing techniques may fail to provide sufficient protection. If this occurs, the energy may be great enough to cause an electronic device, etc. to explode. Realizing this, electronic devices are typically surrounded by some form of a physical enclosure. If and when an explosion occurs the enclosure traps the force of the explosion, and any pieces of an exploded electronic device, inside the enclosure to prevent injury to persons or property outside the enclosure.
Unfortunately, existing enclosures do not provide an acceptable amount of protection when a direct lightning strike or a high-energy, indirect lightning strike occurs. More particularly, laboratory tests have shown that existing enclosures do not provide an adequate amount of protection when a lightning strike generates a current of 60,000 amps over an 80-20 millisecond time period.
Accordingly, it is desirable to provide for enclosures which can provide protection to persons and property when such lightning strikes occur.
We have recognized that persons and property may be protected from lightning strikes by providing an enclosure for an electronic device or the like which includes, on an inner surface, one or more energy absorbing protrusions. If and when an explosion occurs, the protrusions absorb much of the force of the explosion. By so absorbing and/or dispersing the explosive forces, the inventive enclosures prevent harm to surrounding persons or property.
The inner surface, which includes the protrusions, may be combined with an outer surface to form a wall (“first wall”) of the enclosure.
We have also recognized that added protection may be afforded persons and property by adding a second wall which substantially surrounds the first wall and adding one or more types of an energy absorbing material, such as an epoxy, concrete, sand, or some combination of the three, in between the second wall and the first wall.
Referring now to
To reduce the dangers resulting from the explosive forces generated by lightning strikes, the enclosure includes one or more protrusions 5 on an inner surface 3 of enclosure 1.
In one alternative example of the present invention, the protrusions 5 extend inward toward the center of the enclosure 1 which is typically where an electronic device, and therefore the source of an explosion, is centered. When an explosion occurs, the explosive forces impinge on the protrusions 5 and are absorbed, sometimes forcing the protrusions outward.
Though the protrusions 5 in
As shown in
For illustrative purposes only, the width of each protrusion 5 may be 6 to 8 inches wide, the height may be 3 inches tall, and the distance between protrusions may be ¾ inch. Though not shown in
It should also be understood that the number of protrusions used in an enclosure is a design choice. Therefore, the number of protrusions 5 shown in
Before going further, it should be understood that the terms absorb and disperse are sometimes used synonymously or interchangeably herein to describe the ability of the inventive enclosures to reduce the damaging effects of lightning strikes.
The inner surface 3 may be blow-molded with an outer surface 4 to form a wall (“first wall”). The inner and outer surfaces need not be made from the same type of material. For example, the inner surface 3 (including protrusions 5) may be made from a fire-retardant material while the outer surface may be made from an ultraviolet (u/v) material, such as a plastic or the like.
In addition to a first wall 2, enclosures provided by the present invention may comprise additional walls.
Referring back to
Though
In yet another embodiment of the invention, additional walls which substantially surround walls 2 and 7 (not shown in
Backtracking somewhat, the pattern of protrusions shown in the figures may form a step-like pattern for absorbing the explosive energies, etc. generated by a lightning strike. It should-be understood that this pattern is only one of many patterns which may be formed by a plurality of protrusions.
Though the protrusions shown in the figures are depicted as extending inward toward the center of the enclosure, these protrusions may also be orientated in other directions. For example, a protrusion may be orientated in a more parallel direction to a surface, such as an inner surface. In such an arrangement, the protrusions may be perpendicular to explosive forces. Many variations of the orientation of these protrusions may be designed based on a given application and explosive force. In alternative examples of the present invention, some protrusions may extend equally in one direction as another (e.g., equally inward as well as parallel to a surface) while others may extend more inward than parallel, or more parallel than inward.
The above discussion has attempted to set forth some examples of enclosures that provide persons and property protection against explosive forces, etc. resulting from lightning strikes. It should be understood, however, that variations on the above examples may be envisioned and still fall within the scope of the present invention which is determined by the claims which follow.
