US2805466A - Method of manufacturing cartridge casings - Google Patents

Description

Sept. 10, G. A. LYON METHOD OF MANUFACTURING CARTRIDGE CASINGS Filed Dec. 8, 1951 4 Sheets-Sheet 1 P.4C5LZ 2 .4 quj F4 4 JEVJ/ETFZZCJT George AZberz L902? Sept. 10, 1957 G. A. LYON 2,805,456

METHOD OF MANUFACTURING CARTRIDGE CASINGS Filed Dec. 8, 1951 4 Sheets-Sheet 2 Pi E7- 9 29 45 55 r 50 LL .40

' BYE-172L127? George Aiberz Lyon Sept. 10, 1957 G. A. LYON METHOD OF MANUFACTURING CARTRIDGE CASINGS Filed Dec. 8. 1951 4 Sheets-Sheet 3 Sept. 10, 1957 G. A. LYON METHOD OF MANUFACTURING CARTRIDGE CASINGS 4 Sheets-Sheet 4 Filed Dec.

I! rift 2 .1. qmii George Albert Lgqn "nite Patented Sept. 10, 1&5?

METHOD OF MANUFACTURING CARTRIDGE CASINGS George Albert Lyon, Detroit, Mich.

Application December 8, 1951, Serial No. 260,673

4 Claims. (Cl. 29-13) This invention relates to improvements in metallic ordnance shell casings and more particularly concerns improved methods and means for making such casings, and the casings resulting therefrom.

In the manufacture of metallic cartridge shell casings requiring flange structures not only at the base but also at the mouth of the casings, various manufacturing expedients have heretofore been employed, including forging, machining, grinding, attaching collars to the casings, and the like. As a result, such casings have been slow to produce and quite expensive.

An important object of the present invention is to provide an economical and greatly simplified method of making metallic cartridge shell casings, and more especially such casings having flange structure at the mouth or open end of the casing.

Another object of the invention is to provide a novel method of making ordnance shell casings, by coining and drawing operations, even where these casings include flange structure at the mouth end of the casing.

A further object of the invention is to provide a novel apparatus for making shell casings.

Still another object of the invention is to provide novel ordnance shell casing structures.

According to the general features of the invention there is provided, in a new method of making ordnance shell casings, successively drawing a metal blank into tubular form, closed at one end and open at the other end, and at each draw stopping short a predetermined distance from the open end of the casing to provide a collar of material of substantial thickness.

According to other features of the invention, the method also includes the further step of straightening and inwardly shaping the collar at the open end of the casing.

It is another feature of the invention to provide a novel punch and die mechanism for drawing shell casings closed at one end and having a collar at the opposite or open end.

According to a further feature of the invention, a shell casing is provided in one integral drawn piece, comprising a tubular body closed at one end and having the opposite end open, and with the open end provided with a collar in one piece integral with the body.

Other objects, features and advantages of the present invention will be readily apparent from the following detailed description of certain preferred embodiments thereof, taken in conjunction with the accompanying drawings in which:

Figure l is an edge elevational view of a metal blank suitable for drawing a shell casing;

Figure 2 is a vertical sectional view of a casing cup following the first draw of the blank of Figure 1;

Figures 3 and 4 are longitudinal sectional views showing two consecutive further draws of the casing;

Figures 5 and 6 are longitudinal sectional views similar to Figure 4 but showing, respectively, the collar at the open end of the casing inwardly swaged and the casing after it has been machined;

Figure 7 is a more or less schematic view of die mechanism 'used in the drawing of the casing;

Figure 8 is a transverse or diametrical sectional view through 'a further metal blank, following an initial coining thereof to initiate the making of a second casing structure;

Figures 9 and 10 are diametrical vertical sectional views showing successive stages in the drawing of the casing from the coined blank of Figure 8;

Figure 11 is a longitudinal sectional view of the casing of Figure 10, showing successive machining operations thereon;

Figure 12 is a longitudinal sectional view showing an assembly of the casing of Figure 11 with a third casing;

Figure 13 is a transverse cross sectional view through a preliminarily coined blank to initiate the third casing;

Figures 14 and 15 are vertical sectional views showing successive drawings of the blank of Figure 13 into the casing form;

Figure 16 is a fragmentary sectional view of the upper portion of the casing shown in Figure 15 following certain machining operations on the collar thereof;

Figure 17 is a bottom plan view of the casing of Figure 15 following certain machining operations performed thereon; and

Figure 18 is a vertical sectional view of a modification of the structure shown in Figure 12.

As shown on the drawings:

The method of the present invention will be best understood in connection with a description of the several views shown in the drawings.

In drawing a metal shell casing according to the present invention, a metal blank 25 may be initially coined or used directly as a cut blank, depending on the final shape of head desired. Freferably, the blank 25 is circular. If desired, it may be initially formed with a central concave, convex depression or embossrnent 27 which will serve as centering means when placing the blank into a drawing die. 7

The blank of Figure 1 is subjected to successive draws to progressively shape it into an elongated closed end tube or case as represented in Figures 2, 3 and 4, showing successive states of elongation of the casing.

Figure 2 depicts the first draw or cupping of the case, generally identified at 28. In this operation, the marginal portion of the blank 25 is turned axially and provides a tubular side wall 29. One end of the case is closed by a wall 30 providing a base or head, the case being open at the opposite end. The base wall 36 remains of substantially the same thickness as at the conclusion of the initial coining, while the marginal portion of the original blank is worked substantially thinner to afford the necessary elongation in the side wall 29. In the present instance, the base wall 30 is preferably concave-convex.

According to the present invention, the drawing of the case 28 is stopped short of the open end of the casing. As a result, a head or collar 31 of the material of the side wall remains at the mouth of the cup following the first draw as shown in Figure 2. This collar 31 is retained in each of the succeeding draws, which may be two additional draws, as shown respectively in Figures 3 and 4, by which the cup of Figure 2 is substantially elongated to the ultimate length of easing desired, as shown in Figure 4.

It will be observed that throughout the drawing, the side wall 29 becomes successively thinner while the bottom wall 30 remains of substantially the same thickness and the mouth end collar 31 remains of substantially the same thickness or mass of material To accommodate the drawing die mechanism the collar 31. flares radially outwardly.

a 38 provides a substantial annular gap proceeds.

In Figure '7 is shown a drawing die assembly 32 especially adapted for the present purpose. This assembly comprises a preferably stationary die base member 33 having ;a clearance aperture 34-therethroughproviding a passageway .therethrough. :At the upperend' of the aperture -or passageway 34 is mounted aa-drawing die member 35 which maybe of ring-shaped and may "be made from any suitahle hard material .-such ascarboloy.

The die member 35 is seated within a rabbet groove or portion the die'hole 38 is:flared asindicated at 39, preferably frustoconica1ly,lto ,a substantial extent to provide a clearance reception of the collar 31 of the casing as it is I being drawn; 'Itwill be observed that the die hole 38 is of slightly smaller :diameter hole 34.

Operative through the drawing die hole 38 is a drawing plunger or punch 40 having, in this instance, a curvate than the clearance passage 7 tip 41. The punch 40 is operatively supported by a ram 42 for reciprocal stroke movements relative to the die 35.

.In the drawing die mechanism 32, one of the blanks is centered upon the drawing die 35 with the embossment 27, if so equipped, registering with the drawing aperture 38. Then the drawing punch 40 is driven by the ram 42 into the blank to drive the central portion of the blank into the die hole 38 for the first cup draw to start formation of the casing. The drawing stroke of the punch is controlled to stop short of driving the mouth end portion of the side wall 29 into the die orifice 38, thereby. effecting formation of the collar 31.

In each succeeding drawing pass to which the casing 28 is subjected, a longer drawing punch may be utilized, or the strokeof the punch may be controlled to work and elongate the material of the side wall of the casing within successii e permissible elongation limits. It will be observed that the flared entry end 39 of the drawing hole about the drawing plunger 40 to accommodate the collar 31 at the peripheral marginal portion of the drawn casing 28.

As'the punch 40 elongates the casing, a kick-out stud or ejector plunger 43 engages the underside of the base wall of the casing and is depressed as the drawing The kick-out 43 may be carried by a supporting :member 44 resiliently supported by a'set of biasing springs v45, or other mechanical, hydraulic or pneumatic meanswhichyieldin response to the downward pressure against the kick-out plunger 43 during the drawing operation.

At the conclusion of the fcontrolled drawing stroke of the punch 40, the latter is withdrawn from or backed out of the die '35 and'the kick-out plunger 43 follows upwardly to eject the casing 28 with the netracting punch. By preference, the tip -'of the ejector or kick-up plunger 43 is conformed to the outertside of the bottom wall 30, as indicated at 46. 'It will be observed that the clearance afforded by the passage '34 below the die limits kickout resistance on the casing wall 29 and the die is chamfered at 47 at the lower end of the die orifice 38 to facilitate withdrawal of the casing.

' Since the drawn casing will usually stick on the punch V after withdrawal from the die 35, a stripper is provided whichmay comprise a generally inverted U-shaped member 48 which maybe secured as by means of screws 49 to the die base member 33 astride the die member 35.

The stripper'head end ofthe stripper member 48 is disposed at an elevation above the die 35 somewhat greater ture 50 through which the punch 40 operates. As the than the length of the-casing 38 and has a clearance aper- V upper or mouth portion end 31 of the casing 28 strikes against the stripper and comes to a stop, while the punch 40 is withdrawn therefrom.- The casing 28 thendrops down and is removed from the die mechanism.

It will be appreciated that'for small volume production,

one of the die mechanisms 32 may be utilized for all of the plurality of draws, with 'proper control of the stroke of the punch 40 to accommodate :the successive lengths to which the casing is drawn in each progressive drawing pass. However, for large scale production it .will be more expedient to have a 'separate .one-ofthe-die;mechanisms 32 for each draw. j a

At the conclusion of the drawing of the casing 28, .the collar 31 is swaged radiallyinw'ardlyandpreferably uniformly to the general internal diameter of the casing which, as shown in Figure 5, is cylindri-cal. This still leaves a substantial thickness of material projecting uniformlyradially about the mouthpbrtionof the Casin'g, an annular flange ofsubstantial ma-ss. then be machined as desired, forexample, by squaring ofi a shoulder 52 (Fig. '6') on the lowerend'of thecollar' 31 and by machining-a rabbetgroove53 in "the inner side of the collar; 1 The bottom wall 3'0 of are easing may be headed by coining to provide a flat' base surface"54'(Fig. '6) and an internal primer boss 55, as well as a laterally projecting flange 57. Whatever machining necessary to square "the flange 57 and other portionsof the coined {base may be resorted to. r 7

It will thus be seen that the casing 28 comprises, all in one integral piece, a tubular wall structure, a base 'having a lateral flange, and a mouth end portion having a substantial lateral flange 31 opposite the base lateral flange 57. I

The casing shown in Figures '8 to 11, inclusive, is made by substantially the same method as "the casing 28. Initially, as shown in Figure 8, a. metal blank '58 is coined to provide central "depressed embossment 59. having an annular depending marginal flange -0r rib 60. Then, as shown in Figure 9, the coined blank is 'cupped, whereby the marginal portion ofthe blank is drawn to provide 'a tubularside wall 61, while the genenally concave eonvex bottom embossment now provides a "bottom or base wall 7 pending annular rib flange '60 are headed as by'coining' and the flange 'elongatmi and'mac'hined and provided'with external threads 65. j V V A further-operation to which the casing "64 is subjected comprises taper contracting the upper portion ofthe casing to a substantially smaller tapered shape, as. indicated in dash outline in Figure 11. After =this contra cting operation, which also includes-contraction of the collar flange 63, the internal collar flange may benrachined and, where desirable, tapped or otherwise processed; I

The casing 64 is adapted to "be assembled with another casing 68, as shownin Figure 1-2. V I

The various steps in the making of the casing 68 are shown in Figures 13 through '16 and are preferably carried out in substantially the same manner asjin making the casings 28 and 64. Initially, a metal bank 69 isfcoined to provideya central depression land with spaced bosses 71 on the inner side of the depressed-cup and corresponding but offset bosses 72 on the underside of the cup. The coined blan'k is. then :placed in afdrawing press mechanism and the casing started by cupping the same as shown in Figure :14, to provide a tubular wall 73 'and a closed or head wall 74 having the bosses 7'1-an'd 72 thereon. At

aflording The collar 31 can its upper margin, the casing cup 68 has a generally radially outwardly projecting annular collar 75 formed by shortening the drawing in a manner controlled similarly as in making the casings 28 and 64. A second draw elongates the tubular casing wall 73 to the desired extent.

Following the last draw of the casing 68, the bottom wall 74 is headed to flatten the same as shown in Figure 15. Furthermore, the radially outwardly extending collar 75 is swaged radially inwardly as shown in Figure 16 to provide an internal annular flange of substantial mass. This flange is internally tapped or threaded as indicated at 76.

During the heading of the base wall 74, or as a separate operation, the lower end portion of the casing 68 is radially expanded to a slightly larger diameter than the remainder of the casing to provide a radial shoulder 77. To accommodate this, a thickness in the lower portion of the side wall 73 is provided.

As shown in Figures 12 and 17, the base wall bosses '71 and 72 of the casing 68 are located near the margin of the base wall. Between the bosses 72 and preferably axially in the base wall 74, "a hollow embossment 79 is pressed toward the interior of the casing.

Assembly of the casing 68 with the casing 64 may be accomplished in the manner shown in Figure 12, wherein the depending flange 60 of the casing 64 is threaded into the internal threaded collar flange 75 of the casing 68. A ring or band 80 is then secured about the joint between the two casings and is seated in appropriate rabbet grooves 81 and 82 provided complementally and conterminously in the outer adjacent margins of the casing 64 and the casing 68, respectively. Within the rabbet grooves 81 and 82 may be provided radially outwardly projecting prongs 83 which engage in embedded relation in the contiguous inner surface of the band 80. For this purpose the band 80 may be made of a fairly soft material, such as copper, so that by pressing, as by contracting the band into position within the groves 81 and 83, the prongs 83 will embed themselves in the material of the band. This affords a sealing and locking means at the joint between the casings which will resist relative rotation of the casings 64 and 68.

Instead of screwing the flanges 60 and 75 together, such flanges may be simply pressed fitted together, as shown in Figure 18, wherein primed reference numerals indicate similar parts as in Figure 12. In the form of Figure 18, the band 80 serves as an anti-turning and sealing means and also for holding the casings against separation axially.

It may be observed in Figure 12 that the lower end radial shoulder 77 is preferably of about the same diameter as the outside diameter of the band 80 so as to cooperate therewith as guiding means to keep the shell assembly centered in a barrel or tube from which the shell assembly may be fired in use.

The several casings described herein may be made from a suitable material such as steel of any appropriate grade or composition for the purpose intended. On the other hand, the casings or any of them may be made from brass or other metal or alloy.

Where steel is used, spheroidizing may be resorted to, if necessary, but under appropriate circumstances the formation of the casings by coining and subsequent drawing may be accomplished without the spheroidizing treatment.

Each of the several metallic casings described may be drawn in mechanism like the mechanism 32 of Figure 7.

Between the various working steps on the several casings, suitable heat treatment will be employed as desirable, such as annealing, normalizing, and ultimate hardening. The treatment may include the process of my Patent No. 2,059,468, issued November 3, 1936.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

I claim as my invention:

1. A method of drawing metallic cartridge and shell casings, comprising initially cupping a metal blank from an at least marginally flat condition into an elongated tubular walled shell to a point short of the marginal extremity of the blank but turning said marginal extremity into a flaring mouthed undrawn collar, then drawing the tubular wall of the cupped blank to elongate the casing while maintaining said undrawn marginal collar in the substantially original thickness of the same as turned into said flaring mouthed condition, and thereafter sub stantially straightening said flaring mouthed. collar longitudinally of said elongated tubular wall.

2. The method of claim 1 further characterized in that said straightened mouth collar is reshaped to provide a stepped mouth flange of substantially larger diameter than the outside diameter of said elongated tubular Wall.

3. The method of claim 1 further characterized in that said straightened mouth collar is substantially contracted to a substantially smaller diameter than said tubular Wall.

4. In a method of making a metallic casing, drawing a thick sheet metal blank having at least a flat marginal portion into a tubular cup shaped shell closed at one end and open at the other end with a collar of substantially greater diameter than the tubular wall, substantially elongating said tubular wall and reducing the thickness thereof while maintaining said collar of substantially undiminished thickness but with an inside diameter no less than the inside diameter of the elongated wall, heading the closed end portion while said collar is in said inside diameter relationship to the wall, incident to said heading expanding the material of the casing contiguous the closed end to a substantially greater outside diameter than the outside diameter of the tubular Wall, and thereafter reshaping said collar to a smaller diameter than the inside diameter of the elongated wall.

References Cited in the file of this patent UNITED STATES PATENTS 119,900 Van Cleve Oct. 10, 1871 153,358 Mason et a1. July 21, 1874 639,532 Courtman Dec. 19, 1899 1,190,576 Page July 11, 1916 1,278,914 Gruver Sept. 17, 1918 1,310,129 Murray July 15, 1919 1,329,134 Murray Ian. 27, 1920 1,412,794 Penfield Apr. 11, 1922 1,617,491 Mallory Feb. 15, 1927 1,948,437 Bowers Feb. 20, 1934 2,028,996 Sautier Jan. 28, 1936 2,059,468 Lyon Nov. 3, 1936 2,079,102 Biginelli May 4, 1937 2,150,708 Andrews et a1 Mar. 14, 1939 2,237,993 Korbuly Apr. 8, 1941 2,304,582 Lyon Dec. 8, 1942 2,350,491 Butler et al. June 6, 1944 2,360,354 Lyon Oct. 17, 1944 2,418,874 Gary Apr. 15, 1947 2,668,345 Eckstein Feb. 9, 1954 FOREIGN PATENTS 874,975 France Sept. 2, 1942 OTHER REFERENCES American Machinist, July 22, 1943, page 115.

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