1. Field of the Invention
The present invention relates generally to hand guards and accessory rails for firearms.
2. Related Art
Various accessories can be mounted to a firearm, such as an M-16, AR-15, AR-10 or M4 type rifle, using a rail, such as a Picatinny rail system. For example, see U.S. Pat. No. 7,716,865; 7,430,829; 7,685,758 or 2008-0092422. The rail is usually mounted to some portion of the firearm, such as an upper receiver.
It has been recognized that it would be advantageous to develop a hand guard with an integrated rail that is strong, light-weight and stiff.
The invention provides a firearm accessory device in combination with a firearm having a barrel. An elongated tube extends axially along at least a portion of a length of the barrel and extends circumferentially around the barrel. A hand guard is formed by the tube around a bottom and lateral sides of the tube at a proximal end of the tube. An elongated rail is formed by the tube along a top of the tube, a bottom of the tube at a distal end of the tube, a lateral side of the tube at the distal end of the tube, or combinations thereof. The elongated rail is aligned with the shell wall and the barrel, and has a cross-sectional shape orthogonal to the shell wall and the barrel with a narrower neck and a wider head, with the enlarged head being segmented along a length thereof. A monolithic shell wall forms the tube and extends circumferentially around the barrel, and forms the hand guard and the elongated rail, with the shell wall substantially surrounding the barrel in a spaced-apart relationship. An elongated hollow is defined between the barrel and the shell wall, and extends continuously and uninterrupted radially between the barrel and the shell wall, and into the narrower neck of the rail.
In addition, the invention provides a firearm accessory device in combination with a firearm having a barrel. A hand guard is disposed around at least a portion of the barrel and has an elongate shell with an axis aligned with an axis of the barrel. The shell has a shell wall spaced-apart from and circumscribing the barrel. An elongated rail protrudes from the shell and is defined by the shell wall. The rail has an axis aligned with an axis of the shell and the barrel. The rail has a cross-sectional shape orthogonal to the axis with a narrower neck a wider head coupled to the shell by the neck. An elongate hollow is defined by the shell wall with the hollow extending longitudinally between the barrel and the shell wall, and radially between the barrel and the shell wall and into the neck of the rail.
Furthermore, the invention provides a firearm accessory device with an elongated shell having a shell wall adapted to be spaced-apart from and circumscribing a barrel of a firearm and having a longitudinal axis aligned with a longitudinal axis of the barrel. The shell has a portion adapted to be griped by a user and defining a hand guard. The shell wall has another portion protruding radially away from the barrel defining an elongated rail. The rail has an axis aligned with an axis of the barrel. The rail has a cross-sectional shape orthogonal to the axis with a narrower neck a wider head coupled to the shell by the neck.
Additional features and advantages of the invention will be apparent from the detailed description which follows, taken in conjunction with the accompanying drawings, which together illustrate, by way of example, features of the invention; and, wherein:
Reference will now be made to the exemplary embodiments illustrated, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended.
As illustrated in the
The hand guard 14 is disposed around at least a portion of the barrel 20 (
The accessory rail can include an upper rail 16a disposed on the top of the hand guard or device, and a lower rail 14b disposed on a bottom of the hand guard. The upper rail 16a can be formed along the top of the tube, while the bottom rail 16b can be formed along a bottom of the tube at a distal end of the tube. (One or more lateral rails 16c can be formed along one or more lateral sides of the tube and at the distal end of the tube, as shown in
The hand guard 14 and accessory rail 16a and/or 16b are separate and distinct structures with different shapes, sizes, and/or profiles. The hand guard is shaped with broad curvatures and smooth surfaces to be grasped by a user, while the accessory rail is shaped and sized to releasably and lockably receive an accessory. The hand guard 14 can be free of the accessory rail 16a and 16b, or without the accessory rail interfering with the grip formed by the hand guard.
The hand guard 14 and/or rail 16a and 16b are formed by the elongate tube 4 with a longitudinal axis aligned with the axis of the barrel 20. The tube 4 has shell wall 8 spaced-apart from and circumscribing the barrel 20. The shell wall 8 defines and forms the hand guard 14 and rail 16a and 16b. The rail can protrude from the tube or profile of the tube. The tube 4 and shell wall 8 define an elongate annular hollow 44 (
The shell wall can be formed by a composite material with a fiber, such as carbon, in a resin matrix. The shell wall can have a non-uniform thickness extending circumferentially or radially at the rail. The fiber can include various layers of woven mat. For example, a majority of the wall can be formed by eight layers, including inner and outermost layers with fibers oriented at 0 and 90 degrees with respect to the longitudinal axis (or longitudinally and laterally or circumferentially); four intermediate layers of fiber oriented at 45 degrees with respect to the longitudinal axis (or helically in both directions); and two interior layers of unidirectional fibers oriented longitudinally or at 0 degrees. In addition, additional unidirectional, longitudinal fibers, indicated at 50, can be disposed in the rail or head of the rail. The additional unidirectional, longitudinal fibers in the rail can help maintain the stiffness of the rail and hand guard, and can resist relative movement of accessories mounted to the rail. Thus, the fiber density of the wall increases at the rails with respect to the hand guard. The rail can have between 50-80% more unidirectional fibers in one aspect, or 60-70% more unidirectional fibers in another aspect. Such a lay-up can provide a good coefficient of thermal expansion (CTE).
The hand guard can be provided with end caps 60 (
The hand guard described above provides a combined rail and hand guard that is strong, light-weight and stiff.
Referring to
It will be appreciated that the integrated hand guard and accessory rail devices, or firearm accessories, described above can be provides with a single rail, such as only an upper, bottom, or side rail.
The tube or shell wall can have one or more vent holes or apertures 60 extending therethrough. The vent holes or apertures 60 can be located in the lateral side walls. Additional apertures can be formed in the tube or shell wall to accommodate fasteners. For example, separate side rails can be coupled to the side walls of the tube or shell using fasteners.
A method for making the integrated hand guard and accessory rail, or firearm accessory, for a firearm as described above includes obtaining or using an internal mandrel and an external mold. The external mold can have a cavity shaped as an exterior of a hand guard with at least one rail. The external mold can have at least two halves to open and close about the internal mandrel. The internal mandrel can be disposable within the cavity. Thus, an annular cavity is defined between the internal mandrel and external mold to receive fiber and resin. Fiber, such as woven mat fiber and/or unidirectional fiber, is layed-up on the internal mandrel, and inside the cavity of the external mold. The fiber can be pre-preg fiber pre-impregnated with resin. Additional longitudinal fibers can be layed-up in the cavity defining the at least one rail. For example, a woven mat fiber can be layed-up on the internal mandrel and oriented at 0 and 90 degrees. Similarly, a woven mate fiver can be layed-up in the cavity of the external mold and oriented at 0 and 90 degrees. One or more additional woven mat layers can be layed-up on the internal mandrel and oriented at 45 degrees. Similarly, one or more additional woven mat layers can be layed-up in the cavity of the external mold and oriented at 45 degrees. One or more unidirectional mats can be layed-up on the mandrel and/or in the cavity and oriented at 0 degrees. The external mold is closed about the internal mandrel with the fiber therebetween. The mold can be sealed about the internal mandrel. Resin can be injected into the cavity between the internal mandrel and the external mold under pressure. The mold can be opened and the fiber with the resin removed from the external mold and internal mandrel. The resin can cure in and/or out of the mold. Grooves can be cut in a head of the at least one rail, with the grooves oriented transverse to a longitudinal axis of the rail. Other holes for venting or mounting can be cut unto the hand guard.
As used herein, cross-sections are taken orthogonal or perpendicularly to the axis.
While the forgoing examples are illustrative of the principles of the present invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts of the invention. Accordingly, it is not intended that the invention be limited, except as by the claims set forth below.
Priority of U.S. Provisional Patent Application Ser. No. 61/380,644, filed on Sep. 7, 2010, is claimed; and is herein incorporated by reference in its entirety.
Number | Name | Date | Kind |
---|---|---|---|
3090150 | Stoner | May 1963 | A |
6490822 | Swan | Dec 2002 | B1 |
7430829 | Murello | Oct 2008 | B2 |
7584567 | DeSomma et al. | Sep 2009 | B1 |
7685758 | Romer | Mar 2010 | B2 |
7716865 | Daniel et al. | May 2010 | B2 |
7971379 | Robinson et al. | Jul 2011 | B2 |
8276303 | Kapusta et al. | Oct 2012 | B2 |
20050262752 | Robinson et al. | Dec 2005 | A1 |
20060064913 | Gablowski et al. | Mar 2006 | A1 |
20070006509 | DeSomma et al. | Jan 2007 | A1 |
20070163163 | Munst | Jul 2007 | A1 |
20080092422 | Daniel et al. | Apr 2008 | A1 |
20100319231 | Stone et al. | Dec 2010 | A1 |
20120036756 | Brown | Feb 2012 | A1 |
Entry |
---|
Composite Resources; Composite AR-15 Handgaurd for Superior Heat Dissipation—Composite Resources; 2 pages; as accessed Sep. 6, 2011. |
http://www.brownells.com/userdocs/skus/1—100003845—1.jpg; as accessed Aug. 31, 2010; 1 page. |
Remington 870 Picatinny Rail Handguard Rem .870 Handguard Rail—Fab Defense; as accessed Sep. 6, 2011; 1 page. |
TAPCO, Inc. http//:www.ar15pro.com/item/72200—Tapco—inc—grips—pads—stocks— . . . ; as accessed Aug. 25, 2010; 1 page. |
Photo; http://www.ar15outfitters.com/assets/images/(aim-mt021-)12.jpg; as accessed Aug. 31, 2010; 1 page. |
Photo; http://www.gunsholstersandgear.com/wp-content/uploads/2010/05/tapco—ar—handguard—0 . . . ; as accessed Aug. 31, 2010; 1 page. |
Photo; http://images1.tacticalstor.com/750-500-fffff/opplanet-osprey-m4handguard-m-osp-qr1; as accessed Aug. 31, 2010; 1page. |
Number | Date | Country | |
---|---|---|---|
61380644 | Sep 2010 | US |