US2418428A

US2418428A - Cartridge feeding mechanism

Info

Publication number: US2418428A
Application number: US616332A
Authority: US
Inventors: Henning W Rundquist
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1945-09-14
Filing date: 1945-09-14
Publication date: 1947-04-01
Anticipated expiration: 1964-04-01

Description

April 1, 1947.

H. w. RUVNDQUIST 2,418,428

CARTRIDGE FEEDING MECHANISM Filed Sept. 14, 1945 swam/Dom Hamming W Hunflquisfi Patented Apr. 1, 1947 NITED STATES PATENT OFFICE 2,418,428 CARTRIDGE FEEDING MECHANISM Application September 14, 1945 Serial No. 616,332

3 Claims. 1

The present invention relates to an improvement in a feed mechanism particularly adapted for use with, or as a part of, an automatic firearm of the character disclosed in U. S. Patents 1,525,065, 1,525,066, and 1,692,328 issued in the name of John M. Browning, when using a disintegrating belt-link of the type disclosed in copending patent application Serial No. 483,520, filed April 17, 1943, in the name of Harold T. Youngren (now Patent No. 2,392,280) and assigned to the assignee of this invention.

In the operation of automatic firearms of the above referred to type, it has been found that the last link sometimes fails to engage in the guides and as a result the link does not pass out through the link discharge chute but instead passes under the stripper cams and lodges within the feeding mechanism thereby making it necessary to open the feed box and extract the misplaced link before another belt of cartridges can be started through the feeding mechanism.

It is therefore an object of this invention to provide means whereby the last link in a disintegrating-link belt of ammunition being fed through the gun will be positively aligned with, and engaged by, the feed guides in the feed chute thereby assuring that the aforementioned link passes over the stripper cams and out of the discharge slot instead of being deflected under the stripper cams to lodge in the feeding mechanism.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:

Fig. 1 is a perspective view of the cartridge entering side of the feed box of an automatic cannon showing the end of a link belt of cartridges in feeding relationship to such box.

Fig. 2 is a cross-sectional View of the feed box of Fig. 1 showing particularly the relationship of the last cartridge and link of the linked belt of cartridges with respect to the feed box; and

Fig. 3 is a side elevational view of a cartridge positioning spring constructed in accordance with this invention for use in the feed box of Fig. 1.

Disintegrating links I0, used with the above mentioned cannon, comprise a single loop portion I I and a double loop portion l2, joined by a bight portion l3 (Fig. 2). These loop portions are of generally semi-cylindrical form, the double loops being of slightly larger radius than the single loop. Single loop H has a tab [4 on each edge, and double loops l2 each have a tab I5 on their outer edges. Both pairs of tabs are equidistant outwardly from, and parallel to, a plane tangent to the curved side of both single and double loops, the tabs in each pair extending oppositely from each other and parallel to the axis of curvature of the corresponding loop.

Single loop H is slightly narrower than the space between double loops I2, so that when the links ill and cartridges H are assembled into a belt, tabs I4 on single loops l I rest on double loops I2 and tabs IE on double loops l2 extend outwardly, parallel to the axis of the encircled cartridge, for a purpose to be shown later. This relationship is with the links above the cartridges.

Double loops l2 fit so loosely around the cartridge that the link can rotate freely within the range of the angular clearance permitted by the single loop II of the adjacent interlocking link, which loop tightly holds the cartridge in a resilient grip.

A feed box 20, suitably mounted on the cannon (not shown), has a side wall 2|. The side wall 2| is cut away to form a cartridge feed slot 23 (Fig. 2). Stripper cams 26 are provided within feed box 20 facing feed slot 23 as shown in Fig. 2.

A feed chute 29 is attached by bolts 30 to the side wall 2| of the feed box 20 covering teed slot 23, the chute being so disposed that a belt of ammunition fed therethrough will be properly aligned with the stripper cams 26 when it enters the feed box 20.

Feed chute 29 has a floor 3| and a roof 36 (Fig. 2). The outer portion of fioor 3| curves outwardly and downwardly forming a lip 32. Ribs 33 are provided in the floor 3| to act as bearing surfaces for the cartridges being fed therethrough.

The roof 36 of chute 29 curves outwardly and upwardly at the outer edge to form a lip 31 generally above lip 32 on floor 3|. These

lips

32 and 31 serve to guide the ammunition belt into chute 29. Two guides (only one of which is shown in Fig. 2) are secured in spaced parallel relation, to the underside of roof 36, in alignment with stripper cams 26. The guides 38 communicate with guides 34 secured in depending relation to the roof of the interior of the feed box.

As a belt of cartridges is drawn through the feed chute 29, bearing ribs 33 support the car tridges at the required level so that tabs [5 on double loops l2 slide into guides 38 and the belt of cartridges is delivered into the feeding mechanism in proper alignment with stripper cams 2B. In this relation, tabs l5 pass on top of stripper cams 26, whereas the cartridges are engaged by the underside of the cams and thereby stripped 3 from the belt links l and forced down into the loading mechanism (not shown). The structure thus far described is conventional and is more particularly described in U. S. Patents 1,525,065, 1,525,066, and 1,692,328 to John M. Browning.

As the last cartridge enters feed chute 29, the last link, which has its double loop I2 around the cartridge and its single loop II empty, will hang downward from the cartridge, as shown in Fig. 1, there being no support under the empty single loop H. In this position the tabs I5 of such last link would not be engaged by guides 38 but would instead pass under the guides and stripper cams, and, consequently, would be cammed downward by the stripper cams 26 and lodge in the loading mechanism (not shown) To prevent this occurrence, a leaf spring 4|] of generally arcuate shape (Fig. 3) is mounted in feed chute 29 as shown in Fig. 2. One end of this spring is suitably secured to lower lip 32 as by rivets 45 and extends inwardly and upwardly above the floor 3! of chute 29, being constructed so that while it freely deflects under the weight of a cartridge to allow passage of the cartridges thereover, it normally extends high enough to engage the bight l3 of the last link, and is of sumcient stiffness to resiliently cam the link upwardly, in pivotal motion around the last cartridge, into a horizontal position in which tabs [5 on double lops l2 are adjacent the roof 3B of chute 29 and in proper position to be engaged by guides 38 and thereby delivered to stripping cams 26 in position so that the link will be stripped from the cartridge engaged in the double loops [2, and finally discharged through the conventional ejection slot (not shown).

The inwardly projecting end, of. the spring 49 is provided with an angularly bent portion 46. The bent portion 46 passes freely downwardly through a hole 41 in feed chute'fioor 3| when the spring 40 is depressed by a cartridge or link but retains the spring 40 in operative position within the empty feed chute by engagement with the edge of hole 41.

It is therefore apparent that this invention provides simple, yet effective means whereby the last link in a disintegrating-link belt of cartridges is aligned for engagement by the guides and stripper cams so that ejection of the link through the ejection slot is assured.

I claim:

1. In combination with a machine gun having a feed chute secured to the gun and having guides therein arranged to support for movement therethrough the links of a disintegrating link belt of cartridges, the improvement comprising, a leaf type spring, one end of which is fastened to the base of the feed chute, said spring projecting upwardly into the'path of feeding movement of the belt of cartridges, the free end of said spring being constructed and arranged to engage the bottom portion of each successive link whereby said spring biases the last link into proper position for engagement by said guides.

2. In combination with a machine gun having a feed chute secured to the gun and having guides therein arranged to support for movement therethrough the links of a distintegrating link belt of cartridges, the improvement comprising, a leaf type spring, one end of which is fastened to the base of the feed chute, said spring projecting upwardly and angularly forward from its secured end in the direction of feeding movement of the belt of cartridges whereby the free end of said spring lies in the path of feeding movement of the belt of cartridges, the free end of said spring being constructed and arranged to engage the bottom portion of each successive link whereby said spring biases the last link into proper position for engagement by said guides.

3. The combination defined in claim 1 wherein the extreme free end portion of said spring is constructed and arranged to engage the feed chute to retain said spring in operative position in the chute in the absence of cartridge links therein.

HENNING WM. RUNDQUIST.