PT10314U - FIREARM CARTRIDGE AND PROCESS FOR THEIR MANUFACTURE - Google Patents

Abstract

The present invention is intended as a cartridge holder for a firearm, for example, a pinwheel or carabine, which has a set consisting of a chip and a follower mechanism for introducing ammunition loads, one at a time, into the chamber EXPLOSION OF ARMADE FIRE AND THAT CAN BE MANUFACTURED FROM A UNIQUE METAL PART AND HAVE A SOFT INTERIOR FREE OF WELDING AND HAZARDOUS AREAS. The invention also includes a method of manufacturing this cartouche and includes the deep grooving steps and wrapping of the carton body under a substantial pressure using a progressive melting with numerous phases.

Description

DESCRIPTION

FIREARM EQUIPMENT AND PROCESS FOR THE

ITS MANUFACTURE

BACKGROUND AND SUMMARY OF THE INVENTION The present invention relates to a firearm cartridge and to a process for the manufacture of such a cartridge, and relates more particularly to a cartridge and to a process wherein the cartridge has a curved shape and a body constituted, preferably, by a single piece of metal.

This cartridge is used to contain ammunition, for example a series of cartridges, which are introduced one at a time by means of a spring in an explosion chamber of a weapon. The spring maintains pressure in the ammunition to force each cartridge into the blast chamber, and when consumed the cartridge, place the next charge in the fire position.

An example of a firearm that uses a cartridge is the M16 shotgun, which has become a standard shotgun in the United States weapons arsenal and other western countries. There are many variants of the M16 family of rifles, such as M16 / A1, A2, A3 and A4, which are the main infantry rifles used by the United States military and the 15 NATO countries since the early 1960s. These rifles use a cartridge of the type disclosed in this application with respect to the present invention. 1

Preferably, this cartridge is curved and has a substantially rectangular cross-section with longer opposed parallel sides defined by the height of the cartridge used between parallel opposite shorter sides defined by the width of the cartridge. One end of the cartridge is closed with a removable base plate and the other end is opened to allow a cartridge juxtaposed in the gun blast chamber to be placed in the firing position. Preferably, this cartridge is made of steel instead of plastic or aluminum, since the cartridge is subjected to heat and substantial effort when used on the battlefield.

Usually, as in the case of the M16 series of carbines, this cartridge is loaded with about 30 cartridges, weighing about 8.10 grams when filled. This cartridge should fit into the lower receiver, which is on the underside of the weapon, and, so as not to interfere with the operation of the weapon, the cartridge is preferably curved toward the gun barrel relative to the point into the explosion chamber. Preferably, the cartridge has a keyway formed on one of its less thick sides to point and direct the cartridge into a fire position appropriate to enter the blast chamber of the weapon. Typically, the cartridge is constructed by properly folding multiple pieces of metal and spot welding the parts together. These operations are crucial because of the breaking, bending or malformation of the weld or misalignment of the parts that may cause the cartridges to become bent or in extreme cases to fall from the cartridge, making the use of the weapon not effective or dangerous in the field of battle. The correct formation of the keyway is critical: a cartridge with a badly formed keyway 2 may make the cartridge unusable, since the cartridge can not be installed on the bottom of the receiver. Previous technology has disclosed a number of cartridge structures such as:

Alzamora et al U.S. Patent 7,117,626, which relates to a feed aperture pattern for a cartridge;

US Pat. No. 5,461,811, discloses a machine gun body;

Sniezac et al U.S. Patent 5,438,783, which shows a handgun cartridge with breech plate;

Baldus et al U.S. Patent 4,862,619, which defines a cast member or molded for a handgun cartridge;

Chesnut Patent US Pat. No. 4,586,281, for a cartridge designed for use with various weapon styles;

Farrar et al US Patent 4,514,922, showing a cartridge with a special locking mechanism;

Weed US Pat. No. 1,400,252, which illustrates a primitive embodiment of a cartridge.

These references cover a long developmental period of various cartridge and carton features but do not show new constructions and new processes for manufacturing a cartridge which include the references of the present invention which can be used without significant flaws and which is very reliable on the battlefield. Many prior art references have to do with gun cartridges, and these cartridges are not typical of gun cartridges for 3 shotguns or carbines, which are subject to great pressures and situations on the battlefield where the life of the user depends on the effectiveness of the weapon.

Prior art studies on cartridges for these rifles and rifles demonstrate significant levels of failures of the prior art cartridges, sometimes greater than 50% or more, but cartridge studies which the present invention encompasses prove to be free of failures. The curved cartridge case encompassed by the present invention is durable and fabricated of steel to withstand the forces on the battlefield and has a smooth key slot and interior allowing free movement of a charge from the cartridge to the blast chamber of the weapon. These characteristics are achieved using manufacturing means which eliminate roughness and rough areas in the cartridge, as well as by choosing weld points which do not interfere with the movement of the cartridge made by the follower of the cartridge.

In the disclosed process, the die for the cartridge is of high carbon steel, preferably having a Rockwell hardness of 34-38 RC, so that the part does not bend very easily, but is not as hard that renders the material brittle. The cartridge die is designed in such a way that only a single gasket is required to form it, and so that the keyway is free from welds or roughness or the like. This fabrication requires a metal compression operation which stamps and forms the cartridge, including the keyway, in a single operation, preferably using a pressure of 600 tons (but a lower pressure may possibly be used) with an upper pressure pad having a male shaft and a male top block and a female bottom block. Preferably, the pressure pad applies about 2500 kg PSI to the blank sheet by squeezing the piece between the pillow and the male top block and about 4050 kg PSI between the cushion and the female bottom block. If unadjusted pressure is applied, the keyway does not form. If excess pressure is applied, the metal tears.

Preferably, the male shaft has pilots for locating the watch holes on the curved side of the empty cartridge. These pilot holes preferably perform the function of holding the cartridge in place during the stamping and forming operation and during the extension operation. Preferably, the shaped flanges opposite the keyway are used to weld the cartridge body by means of an additive weld, but the position of the weld may be increased so long as it does not interfere with the keyway and does not give rise to rough roughness or rough areas inside the cartridge when it is formed. This stamping and forming operation creates a "U" shaped cartridge body, forming the key slot at the base of " U ". Ribs can be added to the body to remove any roughness from the inside of the cartridge, and these ribs also add resistance to the cartridge and support the bullet as it moves into the cartridge. During the extension operation, an inner flap and an outer flap are formed which run substantially parallel to the keyway enclosing the cartridge and in the welding position.

Robotic welding may be used to weld the edges of the template away from the keyway, and this welding should follow the curvature of the cartridge. After the empty cartridge has become completely formed and welded constituting a single part, a spring and a follower mechanism is introduced into the closed cartridge, and a base plate is applied to close the lower edge of the cartridge.

Objects and Advantages of the Invention It is an object of the invention to provide a curved cartridge for a shotgun or carbine having the features described.

Another object is to provide a curved cartridge that is manufactured as a single piece.

Another object is to provide a body for a curved cartridge which is closed by additive welds.

Another object is to provide a curved cartridge for a weapon which can be heat treated with a nitride or the like to provide a hardened finish.

Another object is to provide a curved cartridge having a substantially smooth interior and free of roughness and rough areas, particularly in its keyway.

Another object is to provide a curved cartridge that is closed by welding on a rim away from its keyway.

Another object is to provide a process for manufacturing a curved cartridge which is embossed and formed on a piece of material with a central key slot 6, with sides depending from said groove and edges spaced apart from the groove to weld the piece of material.

Another object is to provide a process for manufacturing a piece of material from a curved cartridge with a keyway which is formed and stamped by means of high pressure applied on both sides of the piece of material.

These and other objects and advantages will become more apparent upon the continuation of this description, taken in conjunction with the accompanying drawings.

Brief description of the drawings

In the drawings: Figure 1 is a perspective view of a portion of an M16 gun with a cartridge inserted therein and portions withdrawn to show the inside of the explosion zone. Figure 2 is a cross-sectional view of the cartridge made by line 2-2 of Figure 1 showing the follower mechanism in the center of the cartridge. Figure 2A is a detailed cross-sectional view of the cartridge which shows an alternative way to close the cartridge body by welding a short side edge opposite the key slot in the lower edge of a larger side. Figure 3 is an elevation of a short side of the cartridge showing the pilot or pilot holes. Figure 4 is a cross-sectional view of the cartridge made by the line 4-4 of Figure 3 showing the spring, the follower housing and the ribs. Figure 5 is a short side elevation opposite the side of the keyway shown in Figure 3, showing the additive welds closing the body of the cartridge. Figure 6 is a schematic view showing the embossed pieces of material to be formed at the embossing site. Figure 7 is a schematic view showing the formation of the embossed pieces of material. Figure 7A is a cross-sectional view taken along line 7A-7A showing the keyway through a pilot hole. Figure 8 is a schematic view showing the pressure of the meat by placing the ribs and extending the edge section in the body of the cartridge. Figure 9 is a schematic view similar to Figure 8 showing the pressure of the meat by placing the ribs and extending the rim section on the other side of the carton body. Figure 10 is a schematic view showing the installation of the follower, the spring and the spring base in the cartridge, and the installation of the base plate. Figure 11 is a side view of the location of the embossing and forming. Figure 12 is a front view of the stamping and forming location. Figure 13 is a side view of the location of the extension with the piece closed. Figure 14 is a front view of the location of the extension with the open piece.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to Figures 1-5, a cartridge 10 configuring the present invention is installed in a shotgun or a carbine W, in position for entry of a charge of ammunition into the firing area C of the weapon. The ammunition is supplied to the firing area C by means of a spring-loaded follower 11 which moves through the cartridge 10 when each load is placed in the firing position. The cartridge 10 is attached to the weapon W in the receiver R and the cartridge comprises spaced short walls 12 and 13 connected by spaced apart longitudinal walls 14 and 15. In one of the short walls 12 there is formed a key slot 17, and the other short wall 13 constituted by the edge sections 17 and 18 which overlap one another and are fixed by welding. A multiplicity of ribs 19 and 20 are placed opposite and in line with one another on the long walls 14 and 15, and a set of aligned ribs 21 and 22 may be wider and deeper than the other set of ribs. Inside the walls 12-15, the follower 11 is positioned with a head 23, sides 24 and tail 25 slidably inserted in the key slot 16. Preferably, the cartridge body is a single piece and is closed by one or more additive welds. 9

As shown in Figures 3-5, the cartridge 10 has a curved shape 26 and on its short walls 12, 13 has on the side 12 the key slot 16. This tear has a series of pilot or warning holes 27 allowing to see the cartridges inside the cartridge case. At the end of the cartridge 10 remote from the follower 11, the cartridge is closed by a base or bottom plate 28. Inside the cartridge 10 there is a spring 29 fixed at one end to a base 30 which rests on the base plate 28 and at its other end to the follower 11 such that said follower is forced by the spring 29 to raise the cartridges to a position C of the weapon. The additive welds 31 extend along the length of the short wall 13 but leave the interior of the short wall 12 free of flow and additional material. The interior of the walls 12-15 and the keyway 16 are substantially smooth and free of harsh zones so that the ammunition loads can be slidably moved by means of the follower 11 through the cartridge 10 to the firing position C. Alternatively, as shown in Figure 2A, the short wall 13a may be extended and the long wall 14a may be shortened and introduced to allow the short wall border section 13a to bend over the end of the long, welded wall 14a in that place to close the cartridge 10. Figure 4 shows the follower 11 partially withdrawn in the cartridge 10 with the ammunition loads to be drawn by the follower 11 to the top of the cartridge 10.

Preferably, after the cartridge body is fully manufactured, it is hot treated by nitrides. This heat treatment hardens the metal surfaces. 10 II Cartridge manufacturing process

Referring to Figures 6-10, in a sheet metal sheet 45, a piece 40 of more or less rectangular material is formed in said sheet 45 by stamping and puncturing a U-shaped piece of metal from said sheet 45 of metal. Prior to the stamping site, pilot or vigilance holes 27 are formed in the sheet so as to run along the centerline of the carton material piece 40 perpendicular to the travel path of the metal sheet 45. The center line extends from one edge of the metal sheet 45 through the piece 40 of cartridge material which includes the section with the pilot or watch holes 27 to the other edge of the metal sheet 45 approaching a bridge 55. The piece 40 of material for the cartridge is attached to the metal sheet 45 by the bridge 55. The pilot or watch holes 27 are in line with the bridge 55. Each cartridge piece 40 has two parallel long sides 50, 51 to bridge 55 and four short sides 60 approximately perpendicular to long sides 50, 51. At the stamping site, there is a male axle 70. The male axle 70 is equipped with the pilot pins 80. The pilot pins 80 are adjusted so as to correspond to the pilot or warning holes 27. When the male shaft 70 is pressed in a downward direction during the stamping operation, the pilot pins 80 follow through the cartridge piece 40 helping to maintain said piece of material 40 in proper position. During said operation, each short side 60 is angled upwards. The cartridge piece 40 is held in place by a top pressure pad 90 and a bottom pressure pad 100. The male shaft 70 presses downwardly while the female shaft 110 presses upwardly by stamping and forming the piece 40 of cartridge material. After the stamping and forming operation, the cartridge piece 40 remains with the key slot 16 with vigilance or pilot holes 27 rising through the middle of the groove 16. The remaining metal bridge 55 connects the piece 40 of material to cartridge to the sheet or metal strip 45.

As shown in Figure 8, a first pair of short sides 60 are pressed between forming blocks 75, 76 so as to add ribs 19, 21 to one side of the piece 40 of cartridge material and to withdraw the inner flap 17. As shown in Figure 9, a second pair of short sides 60 of the cartridge piece 40 is then pressed by another set of forming blocks 85, 86 so as to add ribs 20, 22 to the other side of the piece 40 of material and remove the outer flap 18. The pressing action, as shown in Figures 8 and 9, by folding the long sides 50, 51 by about 90ø and forming the ribs 19-21, smooths the roughnesses that have been formed in the piece 40 of cartridge material and leads said piece of cartridge material to the final shape of the cartridge 10. Referring to Figure 10, the long side edges 50 and 51 are then welded from the outside of the cartridge piece 40 to close the body 120 of said cartridge. The follower 11 with its head 23, its sides 24, its spring 29, its tail 25, its spring base 30 is then fitted into the body 120 of the cartridge 10. Finally, the base plate 28 is placed in place adjacent the spring base 30 to prevent the follower 11 from leaving and completing the formation of the cartridge 10.

During the stamping and forming operation and the extension operation attention is paid to the piece 40 of cartridge material to avoid rough surfaces and to ensure that the loads move smoothly through the cartridge 10. The cartridge 10 in the embodiment is manufactured in a stepwise molding in a series of steps. Preferably, the steps are as follows: 1. Drilling the pilot holes 27 in the piece 40 of cartridge material. Sufficient pressure should be used to hold the piece 40 of cartridge material and to withdraw said piece 40 of punch material, this pressure being known as the withdrawal pressure. 2. Cut the central portion of the cartridge stock piece 40 using the withdrawal pressure. 3. Cutting the ends of the cartridge piece 40 using the withdrawal pressure. 4. Stamping and forming the cartridge piece piece 40 to create the long, short, and short sides 50, 51 using about 2475 kg of PSI from the top and about 4050 kg of PSI from the bottom, as follows. explained. 5. Formation of the ribs 19-22 and lateral extension of the top edge of the piece 40 of cartridge material using sufficient pressure to maintain flat said piece of material 40 and the extension of the edges 50, 51 with a minimum pressure of about 1800 kg PSI. The rib forming operation and the extension operation can be made separately. 6. Refilling of the piece 40 of cartridge material. The refill adjusts the shape to its final geometry in which the male and female blocks carry the long and short sides of the piece 40 of cartridge material into the cartridge 10. Little pressure is required. 7. Removal of excess material fragments. The roughness of the interior of the body 120 of the cartridge 10 is also withdrawn during the formation of the ribs 19-22 to ensure that there are no rough areas within the cartridge body. The stamping and forming step used in the process is shown in Figures 11, 12, using multiple nitrogen cylinders 130 at the top and multiple nitrogen cylinders 140 at the bottom. The cartridge piece 40 is placed between the upper pressure pad 90 and the lower pressure pad 100 with the male axle 70 overhead and the female axle 110 below. At the time of the pressing operation, the male shaft 70 comes down and pushes the female shaft 110 into a cavity. It is the cavity that contacts the sides. The male axis is adjusted during molding. When the molding is complete, the upper pressure pad 90, as seen in Figure 12, exerts a pressure of approximately 2475 kg PSI on the bottom block 100. The female shaft 110 descends and resists this descent with about 4050 kg PSI. Different cylinders of nitrogen may be used provided they achieve the required pressures. The pressure can be achieved by various means including spring pressure or urethane pressure. Attention should be given to the value of the displacement of the cylinder given the needs of particular displacement distances 14 to the stamping and forming operation of the piece 40 of cartridge material. In the preferred embodiment, four Moeller HR2400-15 nitrogen cylinders are used at the top to create approximately 2475 kg PSI and three Moeller HR1500-100 bottom nitrogen cylinders to create about 4050 kg PSI. As disclosed in Figures 13-14, in the extension step, the top nitrogen cylinders 150 are Moeller HR2400-15 and the bottom nitrogen cylinders 160a are Moeller HR1000-100 and the cylinders 160b are Moeller HR300-100 to extend the long side edges 50 and 51. When the molding is finished, the shell edges 50 and 51 are formed on the two forming axes 200. In Figure 14, the extent setting step is shown with the mold in the open position. The meat boosters 210 force the shafts towards the center of the mold with the flanges 50 and 51 formed on the male axles 200. The pressure-creating devices in this step, in the preferred embodiment, are cylinders which achieve about 900 kg PSI. The parts 170a and 170b are separators. The cartridge is held in the holder 220.

Although many changes and modifications may be introduced into the carton structure and the process of its manufacture within the spirit of the invention, it is not intended that the invention be limited to the exact structure and steps shown and described.

Lisbon, April 18, 2008

Claims (19)

Curved carton for placing loads of ammunition, one charge at a time, in the blast chamber of a firearm, for example a shotgun or carbine, said cartridge having a set of keyway and follower mechanism for moving said charge to said blast chamber, said cartridge having a one-piece body with opposing side walls, said keyway being disposed in one of said side walls, and the locking means of said body being welded on another wall remote from said keyway. Curved carton according to claim 1, characterized in that said body has a smooth interior substantially free of roughness and rough areas. Curved carton according to claim 1, characterized in that said body is made of metal. Curved carton according to claim 2, characterized in that said body is formed from a single sheet of metal. Curved carton according to claim 1, characterized in that said body includes shorter opposing sides and longer opposed sides and said keyway is disposed on one of said short sides. 1 Curved carton according to claim 1, characterized in that the short side of said body opposite the side having said keyway has overlapping edges welded together to close said body. Curved carton according to claim 5, characterized in that a short side of said body opposite said keyway overlaps a border welded to one of said longer sides. Curved carton according to claim 5, characterized in that one of said long sides has ribs etched therein and in that said follower mechanism is arranged to move through said body towards said firing area within the limits of said ribs and said feature. Curved carton according to claim 1, characterized in that said welded closure means comprises additive welds. Curved carton according to claim 1, characterized in that said keyway has pilot holes spaced apart along and extending through its surface. A curved carton according to claim 3, characterized in that the surfaces of said body are hardened. A process for manufacturing the one-piece body of a curved cartridge to place ammunition loads, one charge at a time, in the blast chamber of a firearm, for example a shotgun or carbine, said cartridge a follower mechanism assembly for smooth movement of said load to said blast chamber, characterized in that it comprises the steps of a. forming a piece of cartridge material by removing opposed inverted U-shaped parts opposite a metal strip; B. folding the central portion of the metal strip between the rods of said U-shaped parts removed in the direction of one another; W. stamping a keyway on the bridge between said U-shaped parts; d. extending said rods at an angle of substantially 90ø with said slit bridge and folding a flange on at least one of said rods towards the other of said rods, said flange being spaced from said bridge; and is. welding said edge to the other of said rods to form a cartridge body with opposing shorter sections and opposed longer sections to contain said follower and keyway assembly. A method according to claim 12, wherein said bridge has separate pilot holes and the method comprises the additional step of positioning elements to hold said piece of material in a position chosen by means of said pilot holes. Method according to claim 12, characterized in that the edges of both said rods extend at an angle of 90 ° towards each other so that the edge of one of the rods overlies the edge of the other rod. A method according to claim 12, characterized in that said keyway is etched on its upper and lower surfaces. A method according to claim 12, characterized in that the ribs are formed during said extension and by this extent remove the roughnesses of said piece of material. A method according to claim 12, characterized in that it comprises the additional step of filling said cartridge body formed with a follower mechanism assembly, comprising a spring, a follower mechanism and a base plate to force the loads to enter in said explosion chamber. A method according to claim 12, characterized in that, with the further heat treatment step of said cartridge body, the surfaces thereof are hardened. A method according to claim 12, characterized in that said welding step includes the addition of metallic material during said welding. Lisbon, April 18, 2008 4