FIN STABILIZED PROJECTILE AND LOADING COMPONENTS

A covered projectile that includes a projectile having a nose portion, a middle portion, a rear portion, and a plurality of fins extending outwardly from the rear portion, and a jacket that surrounds at least a portion of the projectile and includes an exterior surface and an interior surface. The jacket includes a front cone. A plurality of annular grooves are defined in the exterior surface of the jacket.

Skip to: Description  ·  Claims  · Patent History  ·  Patent History
Description
CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 62/671,334, filed May 14, 2018, the entirety of which is incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates generally to a projectile, and more particularly to a projectile that includes stabilization fins and for the components for loading the projectile into a cartridge.

BACKGROUND OF THE INVENTION

Standard bullets, projectiles or rounds are cylindrical, pointed objects that are fired from a barrel with rifling therein. The rifling in the bore instills spin and, therefore, stability in the projectile as it travels to its target. As the projectile travels down the barrel a high amount of chamber pressure and friction causes portions of the projectile to be cold formed. This causes the barrel to heat up. The present invention helps solve this problem.

SUMMARY OF THE PREFERRED EMBODIMENTS

In accordance with a first aspect of the present invention there is provided a covered projectile that includes a projectile having a nose portion, a middle portion, a rear portion, and a plurality of fins extending outwardly from the rear portion, and a jacket that surrounds at least a portion of the projectile and includes an exterior surface and an interior surface. The jacket includes a front cone. A plurality of annular grooves are defined in the exterior surface of the jacket. In a preferred embodiment, the middle portion has a greater diameter than the nose portion and the rear portion. Preferably, the projectile defines a projectile axis, each fin includes a front portion that defines a front portion axis and a tail portion that defines a tail portion axis. The front portion axis of each fin extends parallel to the projectile axis, and the tail portion axis of each fin defines an acute angle with the front portion axis.

In a preferred embodiment, the interior surface of the jacket defines a projectile recess and covers the plurality of fins. Preferably, the jacket is comprised of a plurality of jacket sections that are connected by a plurality of seems. Preferably, the projectile recess includes a middle portion, a rear portion, fin portions, and a tail portion.

In a preferred embodiment, the covered projectile includes a casing that defines a casing interior and the covered projectile is positioned such that the front cone and the nose portion of the projectile are positioned outside of the casing, and the annular grooves are positioned in the casing interior. Preferably, each annular groove is defined by a front surface and a rear surface, the front surface is generally perpendicular to an axis defined by the projectile, and the back surface forms an acute angle with the front surface.

In accordance with another aspect of the present invention there is provided a system for loading a covered projectile into a casing that includes a casing die, a preload die, a receiver die and a plunger die. The casing die includes an end protrusion and a central opening extending axially therethrough, the preload die includes a central opening extending axially therethrough and a casing die recess defined therein. The casing die recess is configured to receive the end protrusion of the casing die therein. The receiver die includes a central opening defined therethrough, a plunger die recess defined in a first end, and a casing die recess defined in the second end. The plunger die includes a main body portion that is sized to be received in the plunger die recess in the receiver die, and a plunger extending from the main body portion that is sized to be received in the central opening of the receiver die and the central opening of the casing die.

In a preferred embodiment, the central opening of the preload die is tapered. Preferably, the plunger die includes a pusher portion extending outwardly from a first end of the main body portion. In a preferred embodiment, the system or kit includes at least one projectile assembly that includes a projectile that includes a nose portion, a middle portion, a rear portion, and a plurality of fins extending outwardly from the rear portion, a jacket that surrounds at least a portion of the projectile and includes an exterior surface and an interior surface. The jacket includes a front cone. A plurality of annular grooves are defined in the exterior surface. The front cone and the nose portion of the projectile are positioned outside of a casing into which the remainder of the covered projectile are inserted. The system or kit can also include a barrel that includes threads thereon.

In accordance with another aspect of the present invention there is provided a projectile that includes a front portion that includes a tip, a middle portion that includes a plurality of annular grooves defined therein, and a rear portion that includes a tail and a plurality of fins extending outwardly therefrom. Preferably, the middle portion has a greater diameter than the nose portion and the rear portion. Preferably, the rear portion includes a waist portion and a cone portion and the diameter of cone portion increases between the waist portion and the tail.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be more readily understood by referring to the accompanying drawings in which:

FIG. 1 is a perspective view of a projectile in accordance with a preferred embodiment of the present invention;

FIG. 2 is a side elevational view of the projectile of FIG. 1 in a cartridge;

FIG. 3 is a side elevational view of a covered projectile in accordance with a preferred embodiment of the present invention;

FIG. 4 is an exploded view of the covered projectile of FIG. 3;

FIG. 5 is a perspective view of the projectile from the covered projectile of FIG. 3;

FIG. 6 a side elevational view of the projectile of FIG. 3;

FIG. 7 is an exploded perspective view of the system for assembling the projectile assembly;

FIG. 8 is a cross-sectional perspective view of the casing die;

FIG. 9 is a cross-sectional perspective view of the plunger die;

FIG. 10 is a cross-sectional perspective view of the receiver die;

FIG. 11 is a cross-sectional perspective view of the preload die;

FIGS. 12-24 are a series of cross-sectional views showing the steps for inserting the covered projectile into the casing to create the projectile assembly;

FIG. 25 is a perspective view of a barrel in accordance with a preferred embodiment of the present invention; and

FIG. 26 is a cross-sectional view of the barrel of FIG. 25.

Like numerals refer to like parts throughout the several views of the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description and drawings are illustrative and are not to be construed as limiting. Numerous specific details are described to provide a thorough understanding of the disclosure. However, in certain instances, well-known or conventional details are not described in order to avoid obscuring the description. References to one or an embodiment in the present disclosure can be, but not necessarily are references to the same embodiment; and, such references mean at least one of the embodiments.

Reference in this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the-disclosure. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not other embodiments.

The terms used in this specification generally have their ordinary meanings in the art, within the context of the disclosure, and in the specific context where each term is used. Certain terms that are used to describe the disclosure are discussed below, or elsewhere in the specification, to provide additional guidance to the practitioner regarding the description of the disclosure. For convenience, certain terms may be highlighted, for example using italics and/or quotation marks: The use of highlighting has no influence on the scope and meaning of a term; the scope and meaning of a term is the same, in the same context, whether or not it is highlighted.

It will be appreciated that the same thing can be said in more than one way.

Consequently, alternative language and synonyms may be used for any one or more of the terms discussed herein. No special significance is to be placed upon whether or not a term is elaborated or discussed herein. Synonyms for certain terms are provided. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any terms discussed herein is illustrative only, and is not intended to further limit the scope and meaning of the disclosure or of any exemplified term. Likewise, the disclosure is not limited to various embodiments given in this specification.

Without intent to further limit the scope of the disclosure, examples of instruments, apparatus, methods and their related results according to the embodiments of the present disclosure are given below. Note that titles or subtitles may be used in the examples for convenience of a reader, which in no way should limit the scope of the disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. In the case of conflict, the present document, including definitions, will control.

It will be appreciated that terms such as “front,” “back,” “top,” “bottom,” “side,” “short,” “long,” “up,” “down,” “aft,” “forward,” “inboard,” “outboard” and “below” used herein are merely for ease of description and refer to the orientation of the components as shown in the figures. It should be understood that any orientation of the components described herein is within the scope of the present invention.

Referring now to the drawings, which are for purposes of illustrating the present invention and not for purposes of limiting the same, the figures show various embodiments of bullets or projectiles. FIGS. 1 and 2 show a bullet or projectile 10 that can be loaded into a casing 12 and fired from a standard rifle. In a preferred embodiment, the projectile 10 includes a plurality of fins 14 and a plurality of annular grooves or rings 15 and alternating ridges 16. When traveling down the barrel of a gun, the grooves 15 help form the necessary seal and the fins 14 provide stabilization of the projectile 10 as it travels through the air to the target. It will be appreciated by those of ordinary skill in the art that instead of using a continuous large amount of body to form the seal (as is the case with a standard bullet), the grooves 15 reduce the amount of projectile body or surface area to form the seal.

As is shown in FIGS. 1 and 2, the projectile 10 includes a front portion 18 that includes a tip 20, a middle portion 21 that includes the grooves 15 and ridges 16, and a rear portion 22. The fins 14 extend outwardly from the rear portion 22. In a preferred embodiment, the rear portion 22 includes a cone portion 24 that ends at the tail 26 of the projectile 10. As shown in FIG. 2, the cone portion 24 has a diameter that decreases from the tail 26 forwardly to a waist portion 28. In other words, the cone portion 24 includes an increasing diameter as it extends toward the tail 26. In a preferred embodiment, the diameter of the projectile at the outer surfaces 14a of the fins 14 is less than the diameter of the ridges 16. have an outer surface 14a.

FIGS. 3-6 show a covered projectile 30 that includes a projectile 32 and sabot or jacket 34 and FIGS. 7-11 show a system for loading the covered projectile 30 into a casing 12. FIGS. 3 and 4 show the covered projectile 30 and FIGS. 5 and 6 shows the projectile 32 alone. The jacket 34 includes a plurality of jacket sections 34a, 34b and 34c that surround the projectile 32. The jacket sections are connected along seems. The jacket 34 also includes a plurality of annular grooves or rings 36 and alternating ridges 38 defined in an outside surface thereof (for providing the proper seal). In a preferred embodiment, the annular grooves 36 include a front surface 36a that extends generally perpendicular to the projectile axis A2 and a rear surface 36b that extends at an acute angle (referred to herein as a groove angle G1 and shown in FIG. 3) with respect to the front surface 36a. The groove angle G1 can be any angle between about 1° and about 89°.

It will be appreciated that the geometry and shapes of both the projectile and the jacket may change based on calibers and projectile weights. Fin shape and mass can be modified to move the CG (center of gravity) and increase or decrease rotation and stability in projectile flight. Generally, the system allows the overall shape of the projectile envelope flexibility not achievable in traditional projectiles.

The jacket 34 also includes projectile recess(es) 39 on an inside surface thereof that generally conform to the outer surface of the projectile 32. As shown in FIG. 4, the projectile recess 39 includes a middle portion 39a, a rear portion 39b, fin portions 39c and a tail portion 39d. It will be appreciated that the jacket 34 allows the geometry of the projectile 32 to be modified compared to a standard bullet because there is no dependency on the geometry of the projectile for stabilization in the barrel and/or to provide a gas seal. Instead, these functions are provided by the jacket 34. The jacket 34 also includes a front cone 40 that traps air and causes the jacket 34 to break apart and peel away from the projectile 32 after it exits the barrel. The jacket 34 can be a unitary or monolithically formed piece that surrounds the projectile 32 or can be can include the jacket sections as discussed above. The jacket 34 can be made of Teflon, paper or any material that allows it to tear or peel away from the projectile after exiting the barrel.

As shown in FIGS. 5-6, the projectile 32 includes a nose portion 42 that includes a tip 44, a middle portion 46, and a rear portion 48 that includes a tail 50. Fins 52 extend outwardly from the rear portion 48. In a preferred embodiment, the diameter of the projectile at the outer surfaces 52a of the fins 52 is equal to or less than the diameter of the middle portion 46.

As shown in FIG. 6, each fin 52 includes a front portion 54 that defines a front portion axis A1 that is generally parallel to the projectile axis A2 and a tail portion 56 that defines a tail portion axis A3 that is not parallel to the projectile axis A2 and the front portion axis A1. In a preferred embodiment, the front portion axis A1 and the tail portion axis A3 define an acute angle referred to herein as the fin angle F1. The fin angle F1 can be any angle between about 0° and about 89°. In a preferred embodiment, the fin angle F1 is between 0° and 45°.

FIGS. 7-23 show the system and components for loading the covered projectile 30 into the casing 12. As shown in FIG. 7, generally, the components include a casing die 60, a plunger die 62, a receiver die 64, and a preload die 66. As shown in FIG. 8, the casing die 60 includes a main body portion 68, a central opening 70 and an end protrusion 72. The end protrusion 72 has a smaller diameter or dimension than the main body portion 68. The smaller diameter of the end protrusion 72 creates a shoulder or abutment surface 74. In a preferred embodiment, the main body portion 68 and end protrusion 72 are annular or cylindrical. However, in another embodiment they can be another shape, such as square or other polygonal shape or any other shape provided the end protrusion 72 mates with the preload die 66 and the receiver die 64, as described below. Preferably, the end protrusion 72 is co-axial with the central opening 70.

As shown in FIG. 9, the plunger die 62 includes a stop portion 76, a main body portion 78, a plunger 80, a trough 82 defined between the plunger 80 and main body portion 78 and a pusher portion 84. As shown in FIG. 13, in a preferred embodiment, the end of the plunger 80 includes a concave recess 86 defined therein.

As shown in FIG. 10, the receiver die 64 includes a main body portion 88, a cylindrical portion 90, a central opening 92, an alignment counterbore or plunger die recess 94 and an casing die recess 96 defined between the main body portion 88 and the cylindrical portion 90. As shown in FIG. 11, the preload die 66 includes a main body portion 98, that includes a tapered or conical central opening 100 and an alignment counterbore or casing die recess 102.

FIGS. 12-23 show the method or process for using the components described above to load the covered projectile 30 into the casing 12 to form a projectile assembly 104. As shown in FIG. 12, the casing die 60 and the preload die 66 are used first. As shown in FIG. 13, the preload die 34 is seated on the casing die. When this is done, the end protrusion 72 on the casing die 60 is received in the casing die recess 102 in the preload die 66. As shown in FIG. 14, the rear end of the covered projectile 30 is then inserted into the conical central opening 100 in the preload die 66. As shown in FIG. 15, the casing 12 is then inserted into the central opening 70. The front of the casing 12 has a smaller diameter than the central opening 70 and the rear portion of the casing 12 has a larger diameter than the central opening 70. This allows the front portion of the casing 12 to seat inside the central opening 70.

Next, as shown in FIG. 16, the plunger die 62 and receiver die 64 are used. As shown in FIG. 17, the plunger 80 is inserted into the central opening 92 of the receiver die 64, but the main body portion 78 of the plunger die 62 remains outside of the plunger die recess 94 of the receiver die 64 during this step. As shown in FIG. 18, the receiver die 64 is then mated with the front end of the covered projectile 30. In other words, the covered projectile 30 is inserted into the central opening 92 of the receiver die 64 until a first end 64a of the receiver die 64 contacts a first end 66a of the preload die 66. When this is done, the front end or nose portion 42 of the projectile 32 is received in the concave recess 86 on the end of the plunger 80.

As shown in FIG. 19, the main body portion 78 of the plunger die 62 is then inserted into the plunger die recess 94 in the receiver die 64. This is done by pushing the pusher portion 84. As the plunger die 62 moves toward and into the receiver die 64, the covered projectile 30 is pushed through the central opening 70 of the casing die 60 and part of the way into the casing 12. As shown in FIG. 20, the plunger die 62 and receiver die 64 are then separated from the other dies. As shown in FIG. 21, the plunger die 62 is then pulled part of the way out of the receiver die 64 and the preload die 66 is unseated from the casing die 60 and removed.

As shown in FIG. 22, with the preload die removed, the receiver die 64 is then seated on the casing die 60. When this is done, the end protrusion 72 on the casing die 60 is received in the casing die recess 96 in the receiver die 64. As shown in FIG. 23, the main body portion 78 of the plunger die 62 is then once again inserted into the plunger die recess 94 in the receiver die 64. This is done by pushing the pusher portion 84. As the plunger die 62 moves toward and into the receiver die 64, the covered projectile 30 is pushed further through the central opening 70 of the casing die 60 and fully into the casing 12 to form the projectile assembly 104. The covered projectile 30 can be positioned such that all the grooves are in the casing interior or so that one or more grooves are positioned outside the casing 12. As shown in FIG. 24, the projectile assembly 104 is then pulled out of and separated from the casing die 60. It will be appreciated that the steps described above do not have to be performed in exactly the order described. Furthermore, the assembly components, such as the casing die 60, plunger die 62, receiver die 64 and preload die 66, can be part of an automated system or machine and the steps can be performed automatically or by hand. Furthermore, the assembly components, such as the casing die 60, plunger die 62, receiver die 64 and preload die 66 and/or any of the other components, can be sold as a kit.

FIGS. 25-26 show a gun barrel 106 that can be used with an existing firearm so that it can be adapted to chamber the projectile assembly 104 and fire the covered projectile 30. In a preferred embodiment, the barrel 106 includes threads 108 for connecting to a firearm. In another embodiment, the barrel can be a permanent part of a gun. The barrel includes a chamber 110 and defines a central opening 112 that includes a smooth bore. It will be appreciated that the barrel 106 is removes the rifle lands from a typical barrel, thus leaving a smooth bore and provides a chamber for the assembled round (projectile assembly 104) and a transition area 116 between the chamber 110 and smooth bore 112. The chamber and transition area are uniquely sized for each caliber. It will be appreciated that the covered projectile or fin stabilized sabot round is used to move the projectile velocity closer to the speed of the gas exiting the barrel after ignition.

The barrel 106 can be sold as part of the kit discussed above. The kit can include the barrel 106, a plurality of covered projectiles 30 and/or projectile assemblies 104 and the assembly components, such as the casing die 60, plunger die 62, receiver die 64 and preload die 66.

It will be appreciated that the covered projectile 30 provides lower friction and drag compared to the prior art, which results in lowered friction heating and reduced barrel wear. The fins provide stabilization in flight. A rudder may be included in the fin to augment rotation in flight. The body of the projectile is formed to lower drag in flight and increase airflow in the fin area. As a result, the inventor has found that speed is increased and velocity degradation is reduced. In an exemplary embodiment, the projectile is made of copper, however, any metal or material is within the scope of the invention.

Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise,” “comprising,” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to.” As used herein, the terms “connected,” “coupled,” or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling of connection between the elements can be physical, logical, or a combination thereof. Additionally, the words “herein,” “above,” “below,” and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the above Detailed Description of the Preferred Embodiments using the singular or plural number may also include the plural or singular number respectively. The word “or” in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.

The above-detailed description of embodiments of the disclosure is not intended to be exhaustive or to limit the teachings to the precise form disclosed above. While specific embodiments of and examples for the disclosure are described above for illustrative purposes, various equivalent modifications are possible within the scope of the disclosure, as those skilled in the relevant art will recognize. Further, any specific numbers noted herein are only examples: alternative implementations may employ differing values, measurements or ranges.

The teachings of the disclosure provided herein can be applied to other systems, not necessarily the system described above. The elements and acts of the various embodiments described above can be combined to provide further embodiments. Any measurements described or used herein are merely exemplary and not a limitation on the present invention. Other measurements can be used. Further, any specific materials noted herein are only examples: alternative implementations may employ differing materials.

Any patents and applications and other references noted above, including any that may be listed in accompanying filing papers, are incorporated herein by reference in their entirety. Aspects of the disclosure can be modified, if necessary, to employ the systems, functions, and concepts of the various references described above to provide yet further embodiments of the disclosure.

These and other changes can be made to the disclosure in light of the above Detailed Description of the Preferred Embodiments. While the above description describes certain embodiments of the disclosure, and describes the best mode contemplated, no matter how detailed the above appears in text, the teachings can be practiced in many ways. Details of the system may vary considerably in its implementation details, while still being encompassed by the subject matter disclosed herein. As noted above, particular terminology used when describing certain features or aspects of the disclosure should not be taken to imply that the terminology is being redefined herein to be restricted to any specific characteristics, features or aspects of the disclosure with which that terminology is associated. In general, the terms used in the following claims should not be construed to limit the disclosures to the specific embodiments disclosed in the specification unless the above Detailed Description of the Preferred Embodiments section explicitly defines such terms. Accordingly, the actual scope of the disclosure encompasses not only the disclosed embodiments, but also all equivalent ways of practicing or implementing the disclosure under the claims.

Accordingly, although exemplary embodiments of the invention have been shown and described, it is to be understood that all the terms used herein are descriptive rather than limiting, and that many changes, modifications, and substitutions may be made by one having ordinary skill in the art without departing from the spirit and scope of the invention.

Claims

1. A covered projectile comprising:

a projectile that includes a nose portion, a middle portion, a rear portion, and a plurality of fins extending outwardly from the rear portion, and
a jacket that surrounds at least a portion of the projectile and includes an exterior surface and an interior surface, wherein the jacket includes a front cone, wherein a plurality of annular grooves are defined in the exterior surface.

2. The covered projectile of claim 1 wherein the middle portion has a greater diameter than the nose portion and the rear portion.

3. The covered projectile of claim 1 wherein the projectile defines a projectile axis, wherein each fin includes a front portion that defines a front portion axis and a tail portion that defines a tail portion axis, wherein the front portion axis of each fin extends parallel to the projectile axis, and wherein the tail portion axis of each fin defines an acute angle with the front portion axis.

4. The covered projectile of claim 1 wherein the interior surface of the jacket defines a projectile recess and covers the plurality of fins.

5. The covered projectile of claim 4 wherein the jacket is comprised of a plurality of jacket sections that are connected by a plurality of seems.

6. The covered projectile of claim 4 wherein the projectile recess includes a middle portion, a rear portion, fin portions, and a tail portion.

7. The covered projectile of claim 1 further comprising a casing that defines a casing interior, wherein the front cone and the nose portion of the projectile are positioned outside of the casing, and wherein the annular grooves are position in the casing interior.

8. The covered projectile of claim 1 wherein each annular groove is defined by a front surface and a rear surface, wherein the front surface is generally perpendicular to an axis defined by the projectile, and wherein the back surface forms an acute angle with the front surface.

9. A system for loading a covered projectile into a casing, the system comprising:

a casing die that includes an end protrusion and a central opening extending axially therethrough,
a preload die that includes a central opening extending axially therethrough and a casing die recess defined therein, wherein the casing die recess is configured to receive the end protrusion of the casing die therein,
a receiver die that includes a central opening defined therethrough, a plunger die recess defined in a first end, and a casing die recess defined in the second end, and
a plunger die that includes a main body portion that is sized to be received in the plunger die recess in the receiver die, and a plunger extending from the main body portion that is sized to be received in the central opening of the receiver die and the central opening of the casing die.

10. The system of claim 9 wherein the central opening of the preload die is tapered.

11. The system of claim 9 wherein plunger die includes a pusher portion extending outwardly from a first end of the main body portion.

12. The system of claim 9 further comprising a projectile assembly that includes a projectile that includes a nose portion, a middle portion, a rear portion, and a plurality of fins extending outwardly from the rear portion, a jacket that surrounds at least a portion of the projectile and includes an exterior surface and an interior surface, wherein the jacket includes a front cone, wherein a plurality of annular grooves are defined in the exterior surface, and a casing that defines a casing interior, wherein the front cone and the nose portion of the projectile are positioned outside of the casing.

13. The system of claim 12 further comprising a barrel that includes threads thereon.

14. A projectile comprising:

a front portion that includes a tip,
a middle portion that includes a plurality of annular grooves defined therein, and
a rear portion that includes a tail and a plurality of fins extending outwardly therefrom.

15. The projectile of claim 14 wherein the middle portion has a greater diameter than the nose portion and the rear portion.

16. The projectile of claim 14 wherein the rear portion includes a waist portion and a cone portion, and wherein the diameter of cone portion increases between the waist portion and the tail.

Patent History
Publication number: 20200309491
Type: Application
Filed: May 13, 2019
Publication Date: Oct 1, 2020
Inventor: Leo Berger (Nampa, ID)
Application Number: 16/410,047
Classifications
International Classification: F42B 10/06 (20060101); F42B 5/02 (20060101);