US2899865A

US2899865A - Cartridge feeding mechanism

Info

Publication number: US2899865A
Authority: US
Publication date: 1959-08-18
Anticipated expiration: 1976-08-18

Description

Aug. 18, 1959 R. H. COLBY 2,899,865

CARTRIDGE FEEDING MECHANISM Filed June 27, 1956 3 Sheets-Sheet 1 I 331 1111. 58 5e 60 7 66 25 In M A /V X I l INVENTOR.

Richard H. Bulky BY MZ-JMQMQLQ-MQJ' Aug. 18, 1959 R. COLBY 2,899,855

7 CARTRIDGE FEEDING MECHANISM Filed June '27, 1956 3 Sheets-Sheet 2 IN V EN TOR.

7W5. MCI-614)- Qw- HTI'URNEYS.

Ri EhuIEL Hllulhy I Aug. 18, 1959 R. H. COLBY 2,899,865

CARTRIDGE FEEDING MECHANISM Filed June 27, 1956 3 Sheets-Sheet 5 Fig-'5- 25 36 C if ' .INVEN TOR.

E i EhurflHLnEy CARTRIDGE FEEDING MECHANISM Richard H. Colby, South Hadley, Mass, assignor to the United States of America as represented by the Sec- 3, retary of the Army Application June 27, 1956, Serial No. 594,334

1 Claim. (21. 89-33) (Granted under Title as, US. Code 1952 see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.

' My invention relates to a recoil operated automatic gun and more particularly to a cartridge feeder therefor.

A conventional recoil operated gun is provided with a barrel which is disposed for reciprocation responsive to the discharge of a cartridge therein and a feed device having pawls therein for engaging an ammunition belt to propel the links thereof equal distances to a stripping position therefor respectively responsive to the recoil and counterrecoil operation of the barrel. greater energy which is in the barrel during the recoil stroke thereof, the period of the recoil portion of the ;operating cycle is substantially half the counterrecoil period, resulting in a wide differential in maximum stresses created in the ammunition belt responsive to the pawl operation. Further, a stationary stop is provided .in the feed device for engagement with the cases of car- :tridgesto determine the stripping position thereof.

An object of my invention, therefore, is to provide a i'cartridge feed device for producing substantially equal' stresses on the links of an ammunition belt responsive to the recoil and counterrecoil operation of the feeder.

Another object of my invention is to provide such a feed device operated by a pivoted lever with arms of varied lengths.

A further object of my invention is to provide such ..'a device having a movable stop for engaging the belt links to determine the stripping position of the cartridges.

In carrying out my invention, the recoil and counterrecoil pawls are pivoted and spring-biased on laterally slidable carriages disposedfor opposite reciprocation and .operated by means of a lever in the receiver disposed for a pivotal operation responsive to recoil and counterrecoil of the barrel. j The carriages are joined to the lever at ;'distances from the pivotal center thereof which are in direct ratio with the recoil and counterrecoil periods, to

. substantially equalize the maximum stresses produced in the ammunition belt responsive to operation of the pawls.

A pivoted stop is disposed on the carriage supporting the recoil pawl for cooperation with the counterrecoil pawl to engage the lead link of the ammunition belt in the stripping position therefor.

For better understanding of my invention, reference directed to the following description and the accom 1 'panying'drawings in which:

Fig. 1 is an elevational, partially cross-sectioned view I of the. feeding portion of a gun incorporating my invention;"

Because of the United States Patent O a 2,899,865 Patented Aug? 195.9

Fig. 7 is a view along line 7--7 of Fig. 3 with lever 36 and connector bar 62 disposed axially. 7

Accordingly, a gun 12 having a receiver 14 is provided with a barrel 16 disposed therein for recoil and counterrecoil stroke operation. The velocity of barrel 16 during the recoil'stroke is approximately twice that of the counterrecoil stroke because of the expenditure of the recoil forces during the course of the operating cycle and the absorption of a part of the forces by the engagement of the barrel with a conventional buffer mechanism (not shown) at the end of the recoil stroke.

Gun 12 is suppliedwith cartridges 18 which are releasably engaged in links 20 to form a belt 22 and such belt is fed to the firearm by means of a feeder 24 mounted I on receiver 14. Feeder 24 includes a tray 26 for slidably supporting belt 22 during passage thereof from an feed throat 19 is provided in tray 26 midway of the

ports

21 and 23 to permit transfer of the cartridges 18 from feeder 24 into receiver 14 and the chamber of barrel 16. Mounted to the underside of top portion 25 so as to be spaced therefrom are a rear guide plate 27 and a front guide plate 29. Rear guide plate 27 is provided with ways disposed laterally along the underside thereof to slidingly mount a carriage 28 and a carriage 30 so that carriage 30 is disposed under carriage 28. Extending upwardly from rear guide plate 27 is a cylindrical lug 42 upon which there is pivotally mounted a lever 36. A first pin depends from lever 36 forwardly of lug 42 for extension through a clearance opening in front guide plate 27 to be received by a hole 32 in carriage 28. Hole 32 is suitably elongated to compensate for the longitudinal displacementof first pin 35 therein as lever 36 is pivoted.

32. Second pin 39 is spaced from lug 42 twice the dist'ance which separates first pin 35 from such lug whereby,

' when lever 36 is pivoted, carriage 30 is moved twice the distance that carriage 28 is moved and, consequently, with twice the velocity.

Pivotally mounted to the end of carriage 28, which is adjacent entrance port 21, is a first pawl 44 which is spring biased for sequential engagement with the links 20 for advancing belt 22 into feeder 24 when such carriage is moved awayfrom'such entrance port and such ,fir st pawl is rideable over the links when moved towards such port. Pivotally mounted to the opposite end of carriage 28 is a spring-biased stop 74 which is extendable through an opening 31 in carriage 30 for engagement with the front side of the link 20, which engages the cartridge 18 disposed over feed throat 19, and thereby cooperates with a second pawl 46 pivotally mounted to V the end of carriage 30 which is adjacent entrance port 21 insecuring such link against lateral displacement during extraction of, the cartridge therefrom as by a bolt I (not shown). A depressor 75 is spring-biased into resilient engagement with the link 20 positioned over feed throat 19 to restrain such link against vertical displacement.

' A cylindricalboss '64 extends upwardly from the top 60 mounted for sliding lateral movement along the underside of such front guide plate. Thus, movement of crosshead 60 is transferred by connector bar 62 to lever 36 for simultaneous and opposite movement of

carriages

28 and 30. i

Crosshead 60 is actuated, responsive to reciprocation of barrel 16, by a device including a longitudinally-disposed cylindrical member 50 which is joined by a connector portion 51 to barrel 16 for reciprocation therewith, a tubular member 48 which slidingly receives such cylindrical member and is irnrnovably secured to receiver 14 by a bracket 49 and a collar 52 which is rotatably mounted on such tubular member. Extending upwardly from collar 52 is an arm portion 53 which is terminated by a cylindrical tip 56 rotatably received in a mating groove 58 provided in crosshead 60. A pin follower 54 is slidingly received in an axial bore 57 in arm portion 53 and is biased by a spring 59 into sliding engagement with a cam groove 61 provided in cylindrical member 50 whereby longitudinal reciprocation of such member with barrel 16 is converted to pivotal movement of arm portion 53 which, in turn, is converted to lateral reciprocation of crosshead 60.

The operation of feeder 24 is as follows:

When a cartridge 18 is discharged in barrel 16, the force of the explosion recoils the barrel carrying with it cylindrical member 50 which, through the sliding engagement of pin follower 54 with cam groove 61, rotates collar 52 to pivot arm portion 53 and actuates crosshead 60. The sliding movement of crosshead 60 is translated to pivotal movement of lever 36 by the connection of connector bar 62 therewith and, through such movement of the lever,

carriages

28 and 30 are simultaneously moved in opposite directions. stroke of barrel 16, carriage 28 is actuated to ,move the link 20 engaging the leading one of the cartridges in belt 22 towards feed throat 19 through the engagement of first feed pawl 44 with such link. At the same time, stop 74 is simultaneously moved away from feed throat 19 and into engagement with side 76 of opening 31 to be cammed thereby upwardly and away from engagement with belt 22, as shown in Fig. 6.

Upon the following counterrecoil stroke of barrel 16,

second pawl 46, which during the recoil stroke, was

moved over the leading cartridge, engages the link holding such leading cartridge to complete the passage thereof to feed throat 19. As has been explained hereinbefore, the distance from lug 42 to pin 39 is twice that between Thus, during the recoil such lug and pin 35 and thereby belt 22 is moved one- 0nd pawl 46 into position over feed throat 19, stop 74 0 is moved towards the feed throat from the opposite direction. Thereby, the link holding the leading cartridge is firmly secured over the feed throat between stop 74 and second pawl 46 and beneath depressor 75, as best shown by Fig. 5, when such cartridge is stripped from the engaging link by such means as a bolt (not shown).

Because the distance between lug 42 and pin 39 is twice that between such lug and pin 35, the velocity with which carriage 30 is moved is twice that of carriage 28 and as first pawl 44, mounted to carriage 28, engageably moves belt 22 during the recoil stroke of barrel 16 and as second pawl 46, mounted to carriage 30, engageably 6 moves the belt during the counterrecoil stroke of the barrel, compensation is made for the differences in the velocity of the recoil and counterrecoil strokes of the '4 i I barrel so that a constant force is applied to the b'eltduring the operating cycle of the gun 12 to reduce undesirable stresses in the belt which cause breakages and other malfunctions.

Although a particular embodiment of the invention has been described in detail herein, it is evident that many variations may be devised within the spirit and scope thereof and the following claim is intended to include such variations.

I claim:

In combination with a firearm provided with a receiver, a barrel mounted for reciprocation in the receiver in a recoil stroke and a counterrecoil stroke having a reduced velocity with a predetermined relationship to that of the recoil stroke, and an ammunition belt composed of a plurality of linked cartridges, a feeder for engageably moving the cartridges in the ammunition belt into the firearm and having an entrance port and a feed throat, said feeder including a first carriage and a second carriage in superimposed relationship and slidingly disposed for respective reciprocation between the entrance port and the feed throat, a lever intermediately mounted between the front and rear ends thereof on a vertically disposed lug for oscillating movement in a plane parallel to the path of movement of said first and second carriages, a crosshead slidingly disposed for reciprocation parallel to the movement of said first and second carriages and forward thereof, cam means for converting the longitudinal reciprocation of the barrel to lateral reciprocation of said crosshead, means for connecting said crosshead to the front end of said lever to move such end in the direction from the entrance port to the feed second pin mounted to the rear end of said lever at a distance from the lug which is related to the distance of said first pin therefrom as the velocity of the recoil stroke of the barrel is related to the counterrecoil stroke thereof whereby said first and second carriages are moved simultaneously in opposite directions and are moved with similar velocities during movement thereof away from the entrance port and towards the feed throat, a first pawl pivotally mounted to said first carriage for engagement with the leadingcartridge in the ammunition belt during the recoil stroke of the barrel for unidirectionally moving the leading cartridge from the entrance port towards the feed throat a portion of the distance therebetween, said portion having a relationship to the remaining distance to the feed throat as the velocity of the counterrecoil stroke is related to that of the recoil stroke, and a second pawl pivotally mounted to said second carriage for subsequent engagement with the leading cartridge to continue moving such cartridge to the feed throat at a uniform velocity during the reduced velocitycounterrecoil stroke of the barrel.

References Cited in the file of this patent UNITED STATES PATENTS 709,883 Knight Sept. 30, 1902 2,223,004 Holek Nov. 26, 1940 2,644,365 Maillard July 7, 1953 2,650,520 Lippert et al. Sept. 1, 1.953

FOREIGN PATENTS 897,534 France May 30, .1944