US2789474A

US2789474A - Means for stripping links in a firearm

Info

Publication number: US2789474A
Application number: US256989A
Authority: US
Inventors: Darsie Burns
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-11-19
Filing date: 1951-11-19
Publication date: 1957-04-23
Anticipated expiration: 1974-04-23

Description

April 23, 1957 B. DARSIE 2,789,474

' MEANS FOR STRIPPING LINKS IN A FIREARM Filed Nov. 19, 1951 Qvyuem fom Burn .5 II In-Psi E United States 2,79,414 Patented Apr. 23, 1957 MEANS FOR STRIPPING LINKSIN A FIREARM This invention relates to automatic firearms having a high cyclic rate of fire and more particularly to an improved means for feeding ammunition thereto.

The nature of present day ammunition, the use of disintegrating metallic links for holding the rounds; the requisite of rapid feeding, firing, extraction and ejection with the limited operating energy available impose requirements for delinking the rounds from the link prior; to chambering of such rounds to diminish the energy expended for said delinking.

One of the objects of the instant invention is to provide.

an improved means of delinking present day linked belt ammunition prior to entering the chamber without diminishing the cyclic rate of the firearm.

Another object of the invention is to provide an improved means of feeding linked ammunition to a rotatable feed wheel that supplies delinked rounds to a feedway prior-to said round being chambered by a reciprocating member in a firearm.

A further object of the invention is to eliminate'th'e necessity of having the reciprocating bolt member delink the round in the feedway thereby permitting an uninterrupted and smoother action of such member'du'ring the counter-recoil movement when the round is fed forwardly to its chambered position.

Still another object of this invention provides stripping means for delinking a linked round Without undue strain on the links.

The invention accordingly provides a means of delinking a linked round from a linked belt of ammunition using a link similar to one that is shown and described in Patent 2,480,972, issued September 6', 1949, to R. S. Sanford et al.

These and further objects, which will become more apparent from the following disclosure, are obtained by the unique means illustrated in the accompanying draw ing in which:

Fig.'1 is a schematic cross-sectional end view of the preferred embodiment of this invention; and

Fig. 2 'is a schematic plan view of the feed wheel, one,

of the teeth of the sprockets being cut away to show the linked round and stripper.

Q Referring to the drawings, there is illustrated a portion of a receiver 12 having a feedway 14 in the upper part thereof. A spring-biased cartridge stop 16 is pivotally mounted on feedway 14 of receiver 12 to align a delinked cartridge 18 with the axis of a chamber in a barrel (not shown). Associated with the receiver 12 and conventionally mounted on the side thereof, a housing 20 is belt feeding trough 22, a link chute 24, and a feed Wheel casing 25..

. .65 provided which primarily comprises a cartridge linked A sprocket'or feed wheel 26 is rotata'bly mounted in casing 25 of housing 20 parallel to the longitudinal axis of receiver 12 on a shaft 28 for intermittent movement therewith. Peed wheel 26 comprises two spaced apart sprocket wheels positioned to engage the case of a cartridge. Shaft 28 is intermittently rotated by synchronistic means '(not shown) through an are equivalent to the pitch of the links, i. e., the lateral distance between the center line of adjacent linked cartridges 4%). in the proximity of the feed wheel 26 a suspended support 38 is providedan'd is secured at 32 to wall 34 of casing 25. Support 30 is provided with a leg portion 36 that is positioned contiguous to an upper wall 38 of trough 22 thereby forming an independent upper portion cooperating with trough 22 to position the linked cartridge 40 prior to being fed into feed Wheel 26. Support 30 terminates in a circular portion 42 on the free end thereof contructed to surround shaft 28 and having an outside periphery arranged to coincide with the root of sprocket teeth 68 of feed wheel 26. The periphery of portion 42 y is also provided with a slightly eccentric cam lobe porvti'on 74. Leg portion 36 is provided with an upwardly curved portion 76 disposed forwardly of and adjacent to cam lobe portion 74 for a purpose to be described.

Linked cartridge 40 is reieasably held in a disintegrating metallic link 44 being of the conventional type similar .to the link shown and described in the aforementioned Patent 2,480,972 that interlocks with adjacent links thereby forming a linked belt of ammunition. Link 44 is constructed with a stripper bridge 46 thereby providing a space between a cartridge case when assembled thereto for a I purpose to be described. On receiver 12 there is with a blade-like end 56 that is constructed to pass through the space between the bridge 46 and the case of linked cartridge 40.

Housing 20 is provided with an inclined bottom Wall 58 that connects trough 22 and chute 24 thereby forming a continuous passageway therebetween. The inclination of wall 58 is approximately parallel to an upper surface 60 of end 56 on stripper 48. I A convexed ramp 62 complementary to curved portion 76 of leg 36 is secured tow'all58 immediately before and partially under an arcuate surface 64 on end 56 of stripper 48. Further down on the inclined Wall 58 a link guide 66 is fastened thereon for a purpose to be described later. .1

Referring to Fig. I linked cartridges 40 are fed into trough 22 with the bridge 46 of link 44 downwardly disposed. As linked cartridge 40 is moved intermittently along trough 22 by feed wheel teeth 68 of feed wheel 2 6,'bridge 46 of link 44 is cammed upwardly when passing over ramp 62 thereby forcing the cart-ridge against the curved portion 76 in leg 36 of support 30 thereby con trolling the entrance of the stripper between the cartridge and stripper bridge 46. In the next phase of the feeding cycle the linked cartridge 40 is moved further along trough 22'thereby permitting the arcuate surface 64 to earn the link 44 downwardly partially away from the stripper 48 maintains the bridge against the stripper 48 during the final phase of delinking thereby prolonging the time of engagement of the link 44 with the cartridge. During these functions the cartridge is radially moved along an arcuate configuration 70 that is a continuation of surface 60 on leg 44 and is diametrically positioned from the rotatable center of feed wheel 26. While the cartridge is being delinked, it is releasably held against the configuration 70 by cam lobe 74 on circularportion 42 of support 30 to eliminateany tendency of the partially delinked cartridge from assuming an improper position in relation to the feed wheel 26 during the final operation of entirely removing the link 44 from the cartridge 1%. Cam lobe 74 and configuration 70 also holds the cartridge partially linked until the following round has been engaged by teeth 68 of feed wheel 26. The transitory movements of the linkedcartridge 40 over ramp 62 and guide 66 with the cooperation of curved portion 76 and cam lobe 74 prevents undue strain on link 44 when such link is being partially delinkedfrom cartridge 18 and in conjunction with the contour of stripper 48 the paths of the link 44 and cartridge 18 are both controlled during stripping in such a manner that the clamping elements of the link are of a great assistance in maintaining control of the cartridges until stripping is nearly-completed. Link 44 when free of cartridge 18 falls by gravity down chute 24. Cartridge 1s during successive movements of the feed wheel 26 is carried upwardly by such feed wheel until the cartridges are cammed into feedway 14 by a pivotally mounted spring biased lever mechanism 72 actuated by mechanism (not shown).

While there is shown a particular embodiment of this invention, it will be understood, of course, that I do not wish to be limited thereon, since many modifications may be made and therefore it is contemplated in the appendent claims to cover any such modifications as fall within the true spirit and scope of this invention.

I claim:

1. In a firearm having a transverse feedway, a housing fixedly secured to the firearm adjacent the entrance of the feedway, and rotatable sprocket means mounted in the housing for advancing a belt of linked cartridges therethrough into the feedway, the combination of a feed trough extending into the housing to intersect the bottom portion of the rotative path of the sprocket means, a link chute extending upwardly into the housing to communicate with said feed trough, a stripper fixedly secured to the firearm and having an outwardly projecting blade-like portion extending into said feed trough beneath the sprocket means and into the path of the incoming linked cartridges, cam means in said feed trough for raising a linked cartridge into position to assure entry of said blade-like portion of said stripper between the link and the cartridge, said bladelike stripper portion having an arcuately formed underside for camming the link away from the cartridge during the continuation of the feeding movement thereof, a support fixedly secured at one end thereof in the housing to extend inwardly therein over said feed trough and partially encircle the sprocket means, an eccentric cam on said support for guiding a partially stripped cartridge along the upper surface of said blade,-

like stripper portion and thereby prolonging the interval of actual stripping operation, and cam means in said feed trough adjacent the communicating end of said link chute operative on the partially stripped link to maintain contact thereof with the cartridge associated therewith until the following successive cartridge is positively engaged by the rotating sprocket means. 7 j

2. In a firearm having a transverse feedway, a housing fixedly secured to the firearm adjacent the entrance to the feedway therein, said housing having a feed passage extending along the bottom thereof to terminate in a downwardly extending link chute, a feedwheel rotatably mounted in said housing and having a plurality of sprocket I teeth depending into said feed passage for advancing a belt of linked cartridges therealong, alinkstripper secured to the firearm above'said link chute and having v a projecting bladelike portion extending outwardly along said feed passage into the path of the advancing cartridge belt for entry between each cartridge and the link associated therewith, and cam means in the top and bottom of said feed passage for successively forcing the cartridge and the link associated therewith toward each other during the respective stripping movements thereof to prolong the engagement therebetween until positive engagement of said sprocket teeth with the next following cartridge.

3. In a firearm having a transverse feedway, a housing fixedly secured to the firearm in alignment with the entrance to the feedway, said housing having a feed passage therethrough including a feed trough extending along the bottom thereof and a downwardly extending link chute communicating "with said feed trough, a feedwheel rotatably mounted in said housing and having a plurality of sprocketteeth successively engageable with the ;car tridges in a linked belt for advancing the belt along said feed trough, a support member having one end thereof fixedly secured in said housing and extending above and parallel to said feed trough to terminate at the free end thereof in a feedwheel encircling portion, a link stripper fixedly secured to the firearm above said link chute and having an arcuate upper surface cooperating with said sprocket teeth to guide the cartridges upwardly toward the transverse feedway in the firearm, said link stripper :having a projecting bladelike portion extending outwardly along said feed trough into the path of the advancing cartridge belt for entry between each cartridge and the link associated therewith, said bladelike portion having an arcuate lower surface for initiating the stripping of r the cartridge from the link associated therewith, a cam lobe portion on the feedwheel encircling portion of said support member for camming the cartridge downwardly out of the rotative path imparted thereto by said sprocket teeth and into the link associated therewith to prolong the stripping engagement therebetween, and cam means in the bottom of said feed trough adjacent the entrance to said link chute for forcing the link upwardly toward the partially stripped cartridge to continue to prolong the stripping engagement therebetween until after positive ent gagement of said sprocket teeth with the next following cartridge thereby preventing any discontinuity in the feeding movement of the cartridge belt.

' 4. In a firearm having a transverse feedway, a housing fixedly secured to the firearm at the entrance to the feedway therein, said housing having an entrance for a belt of linked cartridges and a feed trough extending along the bottom thereof in communication with said entrance, a feedwheel rotatably mounted in said housing and having a plurality of sprocket teeth successively engageable -with the cartridges for advancing the belt along said feed trough, a support member having one end thereof fixedly secured in said housing and extending above and parallel to said feed trough to terminate at the free end thereof in a feedwheel encircling portion, a link stripper fixedly secured to the firearm at the end of said feed trough and having an arcuate upper surface cooperating with said sprocket teeth to guide the cartridges upwardly toward the transverse feedway in the firearm, said link I stripper having a projecting bladelike portion extending outwardly along said feed trough into the path of the advancing cartridge belt, a convex cam disposed in the bottom of said feed trough adjacent the projecting end of said link stripper for lifting each linked cartridge into position to assure entry of said link stripper end between 'the cartridge and the link associated therewith, said support member having a concave portion therein in coaxial al gnment with said convex cam to permit the lifting of the linked cartridge, said bladelike stripper portion having a convex underside surface adjacent the free end thereof for forcing the cartridge link out of engagement with the cartridge associated therewith, a camlobe portion on the feedwheel encircling portion of said support member projecting beyond the root periphery of the 2,789,474 5 6 sprocket teeth for camming the cartridge downwardly out discontinuity in the feeding movement of the cartridge of the rotative path imparted thereto by said feedwheel belt. and into the link associated therewith, and an arcuate cam surface in the bottom of said feed trough adjacent References Cited in th file Of this patent the exit thereof for forcing the link upwardly out of the 5 UNITED STATES PATENTS stripping path thereof, said cam lobe portion and said arcuate cam surface being disposed in adjacent relation 2453786 Dixon 1948 to prolong the stripping engagement between the link FOREIGN PATENTS and the cartridge until said sprocket teeth eflect positive 555 267 Great Britain Aug 13 1943 engagement of the next following cartridge to prevent 10