The invention relates generally to the field of electrical power distribution and, more particularly, to an electrical power distribution system for use with a powered rail of a weapon to provide electric power to power-consuming accessories mounted on the powered rail.
It is a problem to reliably provide electric power to power-consuming accessories which are mounted on a weapon in an environmentally hostile environment. The typical adverse natural environment includes, but is not limited to, corrosion, chemical contamination, extreme temperatures, humidity, rain, dirt, ice, and abrasion. The traditional approach is to have each power-consuming accessory completely self-contained, each with its own batteries. However, the weight of the batteries in all of the power-consuming accessories creates an imbalance in the weapon and adds a significant amount of weight to the weapon. That, coupled with the cost of provisioning numerous types of batteries renders self-contained accessories a poor choice. Therefore, the provision of a common power source is a preferred solution. The Powered Rail must have a method of electrically connecting the power-consuming accessory to a common power source which is operationally associated with the weapon.
There are two modes of electrically interconnecting two or more circuit elements together. One mode of electrical interconnection is to hardwire the circuit elements together, which renders the resultant apparatus a unitary structure. The second mode of electrical interconnection is to use one or more electrical contacts to interconnect the circuit elements, thereby enabling the circuit elements to be removably attached to each other and/or to a power source. The electrical contacts are either mounted on mating surfaces of two elements, coming into contact when the two elements are juxtaposed to each other and mechanically forced together, or mounted in connectors, which are electrically tethered to the respective elements via cables, and joined together via locking connector shells which house the respective set of mating electrical contacts and protect the respective sets of contacts from the ambient environment.
The use of electrical contacts mounted on mating surfaces of two elements is optimal for quick connect applications, but these contacts are susceptible to contamination, which degrades performance. The exposed contacts, therefore, must be manufactured from a material that provides low resistivity (such as gold) even when exposed to the hostile ambient environment.
To protect electrical contacts from hostile ambient environmental conditions, such as outdoor applications, the electrical contacts typically are housed in a weatherproof housing, such as a connector shell or a weatherproof sealed box. However, the tethering electrical cable and the connector shell are significantly more expensive than the use of electrical contacts mounted on mating surfaces of two elements, although they provide greater protection from the environment, but are also less convenient for quick connect applications.
Thus, there is presently no power-consuming accessory interconnection system that can be used in a quick connect application on a weapon, which operates in a reliable manner in a hostile ambient environment, is inexpensive, and is long lived.
The above-described problems are solved and a technical advance achieved by the present System For Providing Electrical Power To Accessories Mounted On The Powered Rail Of A Weapon (termed “Weapons Accessory Power Distribution System” herein) which is adapted for use in weapons, such as military weapons. A firearm used in military applications may have a plurality of accessories that can be attached to the weapon, with each accessory having a need for electric power. In order to reduce the weight of these power-consuming accessories, as well as the proliferation of batteries used to power these power-consuming accessories, a common power source is used to power whatever power-consuming accessory is attached to the weapon. One or more powered rails are provided on the handguard, which encircles the barrel of the weapon, to provide a point of mechanical and electrical interconnection for the power-consuming accessories to provide quick connect mounting and dismounting of the power-consuming accessory, absent the use of connectors with their tethering cables, which are susceptible to entanglement. The powered rail(s) are electrically interconnected with a power source, which typically is a battery mounted in the butt stock of the weapon. The power transfer between the power source and the powered rail uses a permanent power distribution system mounted on the weapon, although a pistol grip mounted power source, or a powered rail mounted power source, or an external power source electrically connected to the powered rail are alternatives.
The Weapons Accessory Power Distribution System is designed for use in an unprotected manner where the components are exposed to harsh ambient environmental conditions. The Weapons Accessory Power Distribution System provides the following benefits:
The primary components of this Weapons Accessory Power Distribution System, which is used as an application example, are:
The following description provides a disclosure of the Weapons Accessory Power Distribution System in sufficient detail to understand the teachings and benefits of the Weapons Accessory Power Distribution System, which is delimited by the appended claims.
Contact—One-half of a Contact Pair consisting of an electrically conductive surface which is electrically connected to a power source or power-consuming device.
Contact Pair—A set of two Contacts which, when brought together in mechanical contact, complete an electrical circuit enabling the transfer of electrical power and/or electrical signals therebetween.
Visible Spectrum—The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called “visible light” or simply “light”. A typical human eye responds to wavelengths from about 390 nm to 750 nm. In terms of frequency, this corresponds to a band in the vicinity of 400 THz to 790 THz.
Electrical Resistivity—Electrical Resistivity is a measure of how strongly a material opposes the flow of electric current. A low resistivity indicates a material that readily allows the movement of electrical charge.
Electrical Conductivity—Electrical Conductivity (the inverse of Electrical Resistivity) is a measure of how strongly a material supports the flow of electric current. A high conductivity indicates a material that readily allows the movement of electrical charge.
It is well known to those skilled in the art that rapid fire firearms, utilized particularly in military operations, are characterized by the heating of the barrel of the weapon to relatively high temperatures. At such temperatures, the barrel cannot be safely held by the person firing the weapon. Consequently, a variety of handguards have been developed to shroud the barrel of such rapid fire weapons to enable the person firing the weapon to grip the forward portion of the weapon while mitigating the possibility of burning the hand of the person firing the weapon, yet also providing adequate cooling for the barrel of the weapon.
With particular reference to
The Picatinny Rail was originally designed for use with scopes. However, once established, the use of the Picatinny Rail was expanded to other accessories, such as tactical lights, laser aiming modules, night vision devices, reflex sights, fore grips, bipods, and bayonets. Because the Picatinny Rail was originally designed and used for telescopic sights, the rails were first used only on the receivers of larger caliber rifles. However, their use has extended to the point that Picatinny Rails and accessories have replaced iron sights in the design of many firearms, and they are also incorporated into the undersides of semi-automatic pistol frames and even on grips.
In order to provide a stable platform, the rail should not flex as the barrel heats and cools; this is the purpose of the locking slots: they give the rail considerable room to expand and contract lengthwise without distorting its shape.
Powering the multitude of accessories used on weapons equipped with the Picatinny Rail has been accomplished by equipping each accessory with its own set of batteries. A significant problem with this paradigm is that multiple types of batteries are used for accessories, thereby requiring an extensive inventory of replacements. In addition, the batteries, especially on high power accessories, add significant weight to the barrel end of the weapon, adding strain to the user of the weapon to hold the barrel “on target” in an “off-hand manner” without support for the barrel.
One example of an accessory for a weapon is a scope which includes a reticle which can be illuminated for use in low light or daytime conditions. The reticle is a grid of fine lines in the focus of the scope, used for determining the position of the target. With any illuminated low light reticle, it is essential that its brightness can be adjusted. A reticle that is too bright causes glare in the operator's eye, interfering with his ability to see in low light conditions. This is because the pupil of the human eye closes quickly upon receiving any source of light. Most illuminated reticles provide adjustable brightness settings to adjust the reticle precisely to the ambient light. Illumination is usually provided by a battery powered LED, though other electric light sources can be used. The light is projected forward through the scope, and reflects off the back surface of the reticle. Red is the most common color used, as it least impedes the shooter's night vision. This illumination method can be used to provide both daytime and low light conditions reticle illumination.
Other examples of powered accessories include, but are not limited to: tactical lights, laser aiming modules, and night vision devices.
Butt Stock 21 with Battery Pack 33 (shown in
Power Distribution System 22;
Handguard 23 (optional);
Powered Rail 24; and
Powered Accessory Mounting 25 (shown in
The existing military-style weapon 2 includes in well-known fashion an upper receiver 101, lower receiver 102, barrel 103, muzzle 104, grip 105, and front sight 106. While a military-style weapon is described herein, the teachings of this application are equally applicable to other firearms, such as handguns, fixed mount machine guns, as well as non-weapons based systems. The Weapons Accessory Power Distribution System is added to this standard military-style weapon 2 as described herein.
The Handguard 23 performs the barrel shielding function as in the Picatinny Rail noted above, but has been modified, as shown in
As noted above, the Handguard 23 was developed to shroud the barrel 103 of a rapid fire weapon 2 to enable the person firing the weapon 2 to grip the forward portion of the weapon 2 while mitigating the possibility of burning the hand of the person firing the weapon 2, yet also providing adequate cooling for the barrel 103 of the weapon. Handguards find application in rifles, carbines, and fixed mount weapons, such as machine guns. However, the Weapons Accessory Power Distribution System can also be used in modified form for handguns, as an accessory mounting platform and accessory power source.
One or more of the Powered Rail subassemblies (typically Printed Circuit Boards) 60-1 to 60-4 can be inserted into the respective slots formed in the Powered Rail 24 (on the corresponding facets F1-F4 of the Handguard 23) thereby to enable power-consuming accessories to be attached to the Handguard 23 of the weapon 2 via the Powered Rail 24 on any facet F1-F4 of the Handguard 23 and to be powered by the corresponding Printed Circuit Board 60-1 to 60-4 installed in the Powered Rail 24 on that facet.
The Battery Pack can be implemented in a number of assemblies and mounted on various portions of the weapon (such as on the Powered Rail, or in a pistol grip, or in a remote power source, and the like) as described in the above-noted U.S. patent application Ser. No. 12/689,438 filed on Jan. 19, 2010 titled “Rifle Accessory Rail Communication And Power Transfer System—Battery Pack”. For the purpose of this description,
The Power Distribution System 22 is shown in
An electric wire is routed from the Battery Pack 33 in the Butt Stock 21 to the Powered Rail 24. The external wiring is housed inside a durable and impact resistant polymer shroud 108 that conforms to the lower receiver 102. The shroud is securely retained by a quick connect/disconnect pivot and takedown pin 111 as well as the bolt release roll pin 109 in the trigger/hammer pins 110. The shrouded power cable runs from the battery power connector 107 at the Butt Stock 21 to the Power Rail connector 202. This design provides an easy access for replacing or repairing the cable assembly and eliminates snag hazards or interferences with the rifle operation and requires no modifications to the rifle lower receiver 102 housing.
The Powered Rail 24 is used to electrically interconnect a power source (Battery Pack 33) with the various accessories mounted on the Powered Rail 24, such that the Powered Rail 24 of the Handguard 23 provides the mechanical support for the accessory and the Powered Rail 24 also provides the electrical interconnection. In this example, the Powered Rail 24 is attached to and coextensive with the Handguard 23 sections, such that the mounting of a Power-Consuming Accessory on the Powered Rail 24 results in simultaneous mechanical and electrical interconnection.
As noted above, the Powered Rail 24 comprises one or more Printed Circuit Boards (60-1 to 60-4) which are mounted in the apertures formed in a successive plurality of locking slots on the Powered Rails 24 to carry power to power-consuming accessories which are mounted on the Powered Rail 24 at various locations. The Printed Circuit Boards (60-1 to 60-4) are soldered to electrically conductive busses 72, 74. In addition, a conductive pin connector 73 includes a terminal portion at one end which is pressed into the mating hole (not shown) in the interconnect electrical bus 72. Retaining clips 71 are manufactured from resilient metallic spring material, which are anchored on the upper rail connector 75 and a clamp hook feature of the retaining clip 71 is used to securely hold the lower rail connector 76 by engaging features 77 formed on the lower rail connector 76.
The positive 62P-3, 62P-10, 62P-13 (for example) and negative 62N-3, 62N-10, 62N-13 contacts (on
An ideal electrical connector has a low contact resistance and high insulation value. It is resistant to vibration, water, oil, and pressure. It is easily mated/unmated, unambiguously preserves the orientation of connected circuits, reliable, and carries one or multiple circuits. Desirable properties for a connector also include easy identification, compact size, rugged construction, durability (capable of many connect/disconnect cycles), rapid assembly, simple tooling, and low cost. No single electrical connector has all of the ideal properties. The proliferation of types of electrical connectors is a reflection of the differing importance placed on the design factors.
From a light reflectivity standpoint, the selection of low resistivity metals to construct the contact contradicts with the goal of achieving low light reflectivity. In particular, gold is highly conductive and makes an excellent choice for a contact, but has a high light reflectivity. If coatings are applied to a gold contact to reduce the light reflectivity, the resistivity of the contact is increased and the coatings quickly wear off in a hostile ambient environment where there are many connect/disconnect cycles. Mechanically modifying the surface of the gold to reduce the flat light reflecting plane presented to incoming visible light also reduces the conductivity of the contact and fails to achieve adequate reductions in light reflectivity reduction. Similar problems are encountered with attempts to alloy gold with other metals.
Therefore, existing methods of modifying highly conductive metal contacts to reduce light reflectivity are ineffective.
The selection of a wire mesh to implement the electrical contacts is dictated by the need to provide a low light reflectivity characteristic for the exposed electrical contacts. The need for low light reflectivity is important in certain applications, such as military weapons. In addition, the Low Reflectivity Contact provides a target of dimensions which enable the mating Contact of the Contact Pair to complete the circuit connection without the need for precise spatial three-dimensional alignments of the two Contacts of the Contact Pair.
Thus, the present Low Reflectivity Contact minimizes light reflectivity by the use of a conductive mesh grid which is attached to an underlying conductive surface. The conductive mesh grid comprises a substantially planar structure, typically a matrix of interconnected wires with apertures formed between the intersecting wires, and is used to form the outer surface of the electrical contact. The weave density, weave geometry, and wire diameter of the conductive mesh grid maximizes the attenuation of reflected light in the visible spectrum, yet maintains high electrical conductivity and a lack of sensitivity to contamination via the choice of materials used to implement the Low Reflectivity Contact.
There has been described a Weapons Accessory Power Distribution System. It should be understood that the particular embodiments shown in the drawings and described within this specification are for purposes of example and should not be construed to limit the invention, which is described in the claims below. Further, it is evident that those skilled in the art may make numerous uses and modifications of the specific embodiment described without departing from the inventive concepts. Equivalent structures and processes may be substituted for the various structures and processes described; the subprocesses of the inventive method may, in some instances, be performed in a different order; or a variety of different materials and elements may be used. Consequently, the invention is to be construed as embracing each and every novel feature and novel combination of features present in and/or possessed by the apparatus and methods described.
This application is a continuation of U.S. patent application Ser. No. 12/950979 filed on Nov. 19, 2010, titled “System For Providing Electrical Power To Accessories Mounted On The Powered Fail Of A Weapon”, which is a continuation-in-part of U.S. patent application Ser. No. 12/791,460 filed on Jun. 1, 2010 titled “Rugged Low Light Reflectivity Electrical Contact”, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/183,250 filed on Jun. 2, 2009 entitled “Non-Reflective, Conductive Mesh, Environmentally Robust Electrical Contacts.” This application is also a continuation-in-part of U.S. patent application Ser. No. 12/689,439 filed on Jan. 19, 2010 titled “Rifle Accessory Rail Communication And Power Transfer System—Power Distribution”, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/145,228 filed on Jan. 16, 2009; U.S. patent application Ser. No. 12/689,430 filed on Jan. 19, 2010 titled “Rifle Accessory Rail, Communication, And Power Transfer System”, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/145,248 filed on Jan. 16, 2009; U.S. patent application Ser. No. 12/689,436 filed on Jan. 19, 2010 titled “Accessory Mount For Rifle Accessory Rail Communication And Power Transfer System—Accessory Attachment”, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/145,216 filed on Jan. 16, 2009; U.S. patent application Ser. No. 12/689,437 filed on Jan. 19, 2010 titled “Rifle Accessory Rail Communication And Power Transfer System—Communication”, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/145,232 filed on Jan. 16, 2009; U.S. patent application Ser. No. 12/689,438 filed on Jan. 19, 2010 titled “Rifle Accessory Rail Communication And Power Transfer System—Battery Pack”, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/145,211 filed on Jan. 16, 2009; and U.S. patent application Ser. No. 12/689,440 filed on Jan. 19, 2010 titled “Rifle Accessory Rail Communication And Power Transfer System—Rail Contacts”, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/145,222 filed on Jan. 16, 2009. The foregoing applications are hereby incorporated by reference to the same extent as though fully disclosed herein.
This application is sponsored by the US Department of Defense under Contract Numbers W15QKN-08-C-0072 and W15QKN-09-C-0045.
Number | Date | Country | |
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61183250 | Jun 2009 | US | |
61145228 | Jan 2009 | US | |
61145232 | Jan 2009 | US | |
61145211 | Jan 2009 | US | |
61145222 | Jan 2009 | US |
Number | Date | Country | |
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Parent | 12950979 | Nov 2010 | US |
Child | 13370629 | US |
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Parent | 12791460 | Jun 2010 | US |
Child | 12950979 | US | |
Parent | 12689439 | Jan 2010 | US |
Child | 12791460 | US | |
Parent | 12689430 | Jan 2010 | US |
Child | 12689439 | US | |
Parent | 12689438 | Jan 2010 | US |
Child | 12689430 | US | |
Parent | 12689440 | Jan 2010 | US |
Child | 12689438 | US | |
Parent | 12689439 | Jan 2010 | US |
Child | 12689440 | US |