US2021498A - Ammunition - Google Patents

Description

Nov. 19, 1935. A. CAMPB ELL 2,021,498

I AMMUNITION Filed March 16, 1934 Fig 1 IN VEN TOR.

ALLAN CAMPBELL MW fiTORNEY Patented Nov. 19, 1935 UN ETED STAT PATENT OFFICE AMMUNITION of Delaware Application March 16, 1934, Serial No. 715,831

7 Claims.

This invention relates to anvils for ammunition primers, and contemplates certain improvements in the form of anvils with a view to improving their functioning and simplifying their manufacture.

In Patent No. 1,900,159, March '7, 1933, the present inventor has disclosed an improved form of conical anvil provided with a tip projecting from the apex of the cone and sharp edged ridges extending from this tip and merging with the body of the cone. Anvils of this form are eminently satisfactory for many types of metallic ammunition, but dies for their formation are necessarily somewhat complex and difficult to make. Moreover, the projecting ridges provide a degree of sensitiveness which for many primers is unnecessary. The present invention contemplates an anvil of simpler form which is nevertheless provided with sharp ridges so positioned as to furnish the abrasion required for proper ignition of the priming mixture.

In the drawing:

Fig. 1 is a fragmentary sectional elevation of a cartridge provided with an anvil embodying the present invention.

Fig. 2 is a plan view of the anvil.

Fig. 3 is a side view of the anvil.

Fig. 4 is a sectional elevation of the anvil.

In all of the figures, particularly Figs. 2, 3 and 4, the anvil is shown as greatly enlarged.

The process of manufacturing anvils of this type comprises swaging and cutting them from sheet stock. According to one method, the anvil body or point is first swaged to shape and the periphery of the base is subsequently severed from the sheet. The resulting anvil comprises a base I having substantially the thickness of the sheet from which it is swaged and cut. The cutting dies are of such form as to provide flash passages ll, preferably extending inwardly from opposite sides of the base Ill. The peripheries of the remaining portions of the base It) may be cylindrical surfaces, as illustrated in Patent No. 1,900,159, or portions of these cylindrical surfaces may be cut away orflattened, as shown at 12 (Fig. 2), leaving only short cylindrical areas I 3 between the flattened surfaces 12 and the flash passages H.

The anvil is designed to be received in a cylindrical primer cup M (Fig. 1) .and an improved engagement of the anvil with thecup is secured by the provision of the spaced and restricted contacting areas l3.

Extending above the base H1 is the body l5 of the anvil which, according to the present invention, has the shape of a truncated pyramid, terminating in a substantially flat top or point Hi. In the drawing, a square pyramid has been illustrated, but the invention contemplates a pyramid of any cross-sectional configuration. The corners 5 I! of the pyramid extend from the point l6 and merge with the upper surface of the base .10. These corners furnish abrading ridges which facilitate the ignition of the priming composition under blow. The configuration of the anvil 10 swaging die is such as to form a conical recess I8 within the base 50 and a portion of the body IS. The metal bounding this conical-recess is cut away at the flash passages H, forming the cross-sectional shape illustrated in Fig. 4.

The dies required for the production of anvils of the shape are obviously simple to make and easy to maintain, and the anvils have been found to be remarkably effective in the ignition of ammunition primers.

Resort may be had to variations in many of the details without departure from the spirit of the invention or the scope of the appended claims.

What is claimed is:

1. An anvil comprising a base of extended area .25 and a body projecting from said base, said body being a truncated pyramid terminating in a point of restricted area.

2. A sheet metal anvil comprising a base hav- I ing side portions adapted for engagement withthe periphery of a cylindrical cup, flash passages in said base, and a body extending from said base, said body being a truncated pyramid terminating in a point of restricted area.

3. A sheet metal anvil comprising a hollow interiorly conical base having exterior side portions adapted for engagement with the periphery of a cylindrical cup, and a pyramid shaped body extending from said base and terminating in a point of restricted area, whereby the corners of 40 stricted area, whereby the corners of said pyra- '7 mid form abrading ridges extending downwardly 5c and outwardly from said point. g

r 5. An anvil formed of sheet metal and comprising a base of substantially the thickness of the sheet from which it is formed, the periphery of said base being shaped to furnish a plurality of'55 spaced limited areas of contact with the periphery of a cylindrcal cup, flash passages extending through said base,arecess in said base and a pyramid shaped body extending from said base in substantial alignment with said recess.

6. An anvil formed of sheet metal and comprising a base of substantially the thickness of the sheet from which it is formed, the periphery of said base being shaped to furnish a plurality of spaced limited areas of contact with the periphery of a cylindrical cup, flash passages extending through said base, a recess in said base, and a pyramid shaped body extending from said base in substantial alignment with said recess,

the corners of said pyramid shaped body intersecting said flash passages.

7. An anvil formed of sheet metal and comprising a base of substantially the thickness of the sheet from which it is made, a recess in said base, a body extending from said base in substantial alignment with said recess, flash passages cut in said base and communicating with said recess, said body being a truncated pyramid having a point of restricted area, the corners of said pyramid forming abrading edges extending downwardly and outwardly from said point and intersecting said flash passages.

h ALLAN CAMPBELL.

Images