Patent Application
20130341553
Not Applicable
Not Applicable
Not applicable
Thermal Suppression Device
The present invention relates generally to the suppression of thermal radiation, such as the radiation emitted from fire arms, explosives, exhaust or similar situations where it would be advantages to suppress thermal radiation in such a way that the radiation blends into the ambient environment. More particularly, the present invention relates to a phase change system that absorbs the thermal energy, reducing the thermal signature.
Since World War II, tactical camouflage, concealment and deception inventors have been forced to create products and solutions that addressed more than visible light. Products and solutions needed to conceal detectable signatures that humans or any detection system could pick up. This advancement is a result of increasingly sensitive sensor devices and technologies that have been developed over time. These sensing devices include: advanced visual scopes, radar, night vision, satellites, and thermal imagery detection. Further, advances have led to technologies like forward looking infrared imaging technology and shortwave infrared sensing technologies that make thermal signatures easily detectable.
Today virtually every nation and many non-state military organizations have access to advanced tactical sensors for target acquisition (radar, cameras, and thermal imagers) and intelligence gathering surveillance systems (ground, air, and satellite reconnaissance). Precision-guided munitions exist that can be delivered by artillery, missiles, submarines, personnel, and aircraft and that can operate in the IR region of the electromagnetic spectrum. These advanced systems are available through internal manufacturing or purchase on the world market. These advanced systems and sensors allow enemies to acquire and engage targets through visual smoke, at night, and under adverse weather conditions.
In an effort to combat these new sensing and detection technologies, camouflage paint, paint additives, tarps, nets and foams have been developed for visual camouflage and thermal and radar signature suppression.
Paint and paint additives by themselves do not appear to be to provide a desired level of visual camouflage and thermal and radar signature suppression. For example, paint has proven inadequate for rendering high detailed portrayals of complex camouflage patterns in use today, such as ACU and MARPAT, quickly and efficiently. Advanced paint additives and coatings seemed promising, but have unforeseen logistical issues. While it appears that chemical agent resistant coating paint is the ideal paint for camouflage and chemical protection, it is important to realize that the utilization of chemical agent resistance coating paint has many downfalls of its own. Several disadvantages are obvious when using chemical agent resistant coating paint. Chemical agent resistant coating paint is considered environmentally hazardous, and its application requires Environmental Protection Agency approved safety equipment and facilities. Furthermore, many of these apparatuses can only be applied to a limited number of surfaces.
The environmental protection agency regulations restrict the use of chemical agent resistant coating to one quart per site per day. Only approved facilities, such as depot-level maintenance facilities can dispense chemical agent resistant coating in volume. This restriction on volume painting is attributed to the amount of volatile organic compounds released into the atmosphere when spraying. Further, chemical agent resistant coating is expensive and has a limited shelf life. In fact, chemical agent resistant coating is approximately four times more expensive than conventional painting technologies. The logistical and legal issues associated with the use of chemical agent resistant coating paint makes it problematic to repair assets or use without extensive costs to specialized equipment and facilities that are needed to obtain the camouflage from the advanced technologies mentioned above, paints have proven to not be very effective.
Tarps and nets can provide separation between the assets and detection systems used. Tarps and nets can suppress thermal signature as well as signals detected by radar. However, both tarps and nets can be heavy and cumbersome to use. They require significant time to setup or transport and therefore interfere with mobility.
The use of foam appears to have promise regarding thermal and radar suppression. However, foam is difficult to effectively use in such camouflage, concealment or deception applications because the foam is not functional in terms of visual camouflage.
In recent years special operations has become a very important part of military operations. One of the biggest assets of special operations is stealth. Camouflage has been developed so people and military assets can blend into their surroundings. Radar absorbing material has been developed to cloak military assets from radar or similar detections mechanisms. However, one area where camouflage has lacked successful development is suppressing the thermal radiation emitted from firearms or similar devices. Surprisingly, the firearms and similar devices are critical to almost every aspect of military or other special operations where stealth is of importance.
As can be seen, there is a need for a method that can suppress thermal radiation emitted from heat sources in order to remain undetected.
A full and enabling disclosure of the present subject matter including the best mode thereof to one of ordinary skill in the art is set forth more particularly in the remainder of the specification, including reference to the accompanying figures.
The present invention is an improved thermal suppression apparatus, method of operation and means to operate said thermal suppression apparatus that simplifies and improves on current methods of thermal suppression, and stealth technology.
The present invention is an thermal suppression design that is very simple and flexible. The thermal suppression mechanism can be used in all firearms, artillery shells, motors, or any other heat source that is desired to blend in to the surroundings. The thermal suppression mechanism is built using a high specific heat phase changing material that can absorb a large portion of heat generated by the device it is camouflaging. This material may be able to absorb or release a significant amount of heat energy when it undergoes a phase change.
Because the primary objective of camouflage is to blend in with your surrounding there must be a method to change the temperature at which the thermal mass undergoes a phase change. This may be accomplished by a thermal expansion and contraction of the chamber where the phase changes mass is located in. By changing the volume or pressure of the chamber it effectively changes the temperature at which the phase change substance will undergo a phase change. As a result the temperature at which it absorbs the most energy can be very near and just slightly above the temperature of the surroundings. Therefore the phase change thermal suppression device works at a variety of temperatures and can automatically adjust. Moreover, it may be necessary to cool the phase change material so that it reverts to its unheated state at ambient temperature. To accomplish this a cooling device may be used. The cooling device may be any device or configuration that can adequately cool the phase change material, for example a heat sink like device or thermoelectric peltier plate may be used.
The following description is of the best currently known modes of carrying out embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims and appreciation for the new art.
Broadly, an embodiment of the present invention is an apparatus, method, and means to decrease thermal radiation emitted from firearms or similar devices consisting of a phase changing material with a large heat capacity. The thermal suppression mechanism may use phase change materials and the expansion of materials in order to suppress thermal radiation.
Embodiments of the invention are discussed below with reference to
The phase change material 12 is in an operation chamber 14 that is thermally connected to the firing chamber and barrel 16. When the firearm fires the heat from the burning propellant transfers to the phase change material 12 from the barrel 16, the phase change material 12 is heated. The phase change material 12 readily absorbs the heat and undergoes a phase change which increases the effective amount of thermal energy it can absorb.
In order to blend in with your surrounding at any temperature the temperature at which the thermal mass 12 undergoes a phase change is altered by changing the pressure and volume of the phase change material container 14. This is accomplished by the thermal expansion and contraction of material near the chamber where the phase change material mass is located in. The thermal expansion material 18 expands and contracts as it is heated and cooled respectively. The expansion and contraction of the thermal material 18 changes the volume of the phase change material chamber 14. By changing the volume or pressure of the chamber it effectively changes the temperature at which the phase change substance 12 will undergo a phase change. As a result the temperature at which the phase change substance 12 absorbs the most energy can be very near and just slightly above the temperature of the surroundings. The relationship between ambient temperature and phase change temperature is shown in
In further detail, still referring to the invention of
The construction details of the invention as shown in
The thermal suppression assembly 10 may be integrated into the gun barrel, suppressor, or even the munitions themselves. The thermal suppression assembly 10 may also be an attachable device that can be moved and removed and be applicable to many different devices or situations.
Additionally, during a situation which requires the release of a large quantity of thermal energy it may be desired to use a cooling mechanism in order to return the phase change material back to its unheated state quicker than normal cooling would allow. The cooling unit may take on many forms. The cooling mechanism may be passive such as air cooling; it may utilize a heat sink like device or cooling circuit. More specifically, the thermal suppression assembly 10 may utilize a thermo electric device 20, also known as peltier plates to cool the apparatus and phase change material.
More specifically,
Although various shapes, positions, and configurations are not illustrated in the implementation, it should be appreciated that this is not a limitation and that various alternate embodiments can and may be used.
The claimed invention differs from what currently exists. Although there are many inventions that attempt to suppress or mitigate the problems associated with unwanted thermal radiation. There are no similar inventions that use a phase change material in the way described above. Additionally, there are no similar inventions that use a phase change material in conjunction with a variable volume or variable pressure container that modifies the phase change temperature of the phase change material. Moreover, there are no similar inventions that use the thermal expansion or contraction of materials to modify the volume and pressure within the phase change material container to modify the temperature at which the phase change material undergoes a phase change. Previous devices include paint, foam, cooling systems, and cumbersome shielding materials. These devices often prove to be expensive, slow, inconvenient, and often times cumbersome to both install and use.
Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference here in to details of the illustrated embodiments is not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention.
There are many applications for the invention. For example, SOCOM is seeking integrated suppressors for rifle barrels that can hide infrared and thermal signatures when their weapons fire, rendering them invisible to opponents' night vision goggles or similar detection systems. These devices need to work despite the weapons recoil and changes in its barrel temperature. The use of a dynamic volume or pressure phase change chamber allows the device to function at any temperature.
The phase change material may be integrated into each shell casing on a per bullet basis. Multiple embodiments of the present invention may be integrated into suppressors or rifle barrels to reduce infrared and thermal signatures. The reduction of infrared and thermal signatures would allow soldiers and their equipment to blend in with their environment. As a result night vision goggles or thermal imaging systems would be unable to distinguish the soldiers and their equipment from the environment.
The above embodiments have dealt with the thermal suppression mechanism equipped with phase change material and expansion material attached to a thermal source. However, it is obvious that the invention can be applied in different configurations. Further, it needs not be pointed out that the embodiment can be modified in a variety of ways and used within the arts.
