3 the operating parts to be made. The swinging movement of the lever 34 in a counterclockwise direction is terminated by the engagement of a face on the lower side of said lever with a yielding plate 81, mounted in the housing and supported by buffer springs. At the end of the counter-recoil movement of the gun, the cam 66 releases the cam roll 64 and the hook 58 is returned to locking engagement with the pin 60, to recouple the levers 34, 56, by its spring-pressed plunger 62 and by a spring 82 (Fig. 3) ' The spring 82 engages a projection 8,4 on the cam lever 56 and surrounds a vertical pin 86 secured in the housing 10 and extending through an opening in the projection 84. Movement of the cartridges, i.e., the belt, away from the feeder mouth in a direction opposite to he direction of feed is prevented by detents 88 (Fig. 1). The detents 88, as shown in Fig. 5, are pivoted within the housing 10 and extend through openings in the housing into the path of movement of the cartridges. Springs 90 serve to hold the detents 88 in their upward positions in which they prevent reverse movement of the cartridies. During the feed movement of the cartridges toward the feeder mouth, the detents yield downward against the action of the springs 90, permitting the cartridges to pass over them. In order to facilitate removal of the leading cartridge from the belt, by the stripper mechanism described in the afore@mentioned application, when the leading cartridge is in its position above the feeder mouth 16, a link support 92 (Fig. 3) is provided which engages the link portion b6tween the leading and the following cartridge. Tffe link support 92 is mounted below the pusher 18 and the link 30 and has a longitudinal slot 94 through whien extends a fulcrum pin 96 secured in the housing 10. "rhe fuler-um pin 96 permits loiigitudinal movements of the link support 92 as well as swinging movements about its axisi A spring 98 enga.-ing a pin 100 on the inner end of the link support 92 normally swings the link support 92 downward about the axis of the pin 96 and holds it in its operative position in engagement with the top of the right-hand wall forming one side of the feeder mouth 16 ' A projection 102 on the pusher 18 engages in a longitudinal slot (not shown) in the link support 92. When the pusher 18 is moved away from the feeder mouth, the projection 102 first moves idly in the slot of the link support 92. Upon-engaging the end of the slot, however, the pusher carries the link support with it away from the feeder mouth. It is also important,that the link engaging end of the stipport 92 shall not int I erfere with the feed @movement of the next cartridge. Therefore, in moving away frorn the feeder mouth, the link support is simultaneous'iy swung downward about the axis of the pin 96 by the spring 98, along the face of a cam 104 secured within the housiing 10 adj@cent to the right hand wall of the feeder moutn 16. During the feed movement of t-he pusher, the projection 102 again first moves idly iii t@ie slot of the link support 92 and then the link support is again carried forward with the pusher moving upward along the face of the cam 104 into its operative position. T@e operation of the horizontal feed unit of the feed 2,974,569 4 mechanism is as follows. It is assumed that an ammunition belt is passing through the feed mechanism, that the leading cartridge of the belt is in position above the feeder mouth 16 with the pusher IS engaging the rear face of the cartridge and the link support 92 engagin- the link, and that two loose rounds are in the feeder mouth 16 ,vhich en-ages in the ammunition feedway of the gun, the nose of the lower round projecting toward the tube of the gun. Upon firing the gun, the lowermost round is picked up 10 by the forward moving l@reech bolt. Durin.- recoil, the cam 66 moves with the recoiling gun parts and swings the levers 56, 34 in a clockwise direction (Fig. 3) about the axis of the shaft 36'by acting u@on the cqlm roll 64. The pusher 18, carrying the support 92 with it, is con15 sequdntly moved to the right away from the feeder mouth, to a position in which i@ will assume control over another cartridge and the spring 33 : siniultaneously energized. When the projection 74 of the hook 58 en9.0 gages the release plate 76 the hook is swung iipward against the pressure of its plunger 62 out of enga-ei@.ient with the pin 60, thereby releasing the lever 34. The spring 38 now s@vings the lever 34 in a counterclock-wise direction (Fi.-. 3) about the axis of the shaft 36, imparting feed movement to the pusher .18 and moving another 25 car-tridge into position above the feeder mouth 16. In moving toward the feeder mouth, the pusher returns the Iiilk support 92 to its operative position. At the end of the counter-recoil movement the cam lever 56 is released by the cam 66 and the hook 58 is moved from 30 its disengaged position, shown in Fig. 1, into engagemeiit with the pin 60 by the spring-pressed plunger 62 and the spring 82. @ I-@Taving thus described my invention, what I claim as new and desire to secure by Letters Patent of the United 35 States is: In an ammunition feed mechanism adapted to be mounted on an autornatic gun to feed cartridges from a - linked belt to tne ammunition@ feedway @ of the gun, a feeder mouth mounted in the ammunition feedway, a 40 pusher movable between a retracted position and the feeder mouth to bring.successive cartridges into a position above the feeder mouth, a movable link stipport for engaging the link of the cartridge positioned above the feeder mouth, a slot in the link support, a fulcrum pin engaging in the slot and permitting longitudinal and swinging movements of the link support, a lost motion connection between the pusher and the link support for effecting movement of said support with the pusher, a cam for guiding the link support during movement with the 50 pusher, and a spring for maintaining the link support in engagement with the cam@ References Cited in the file of this patent UNITED STATES PATENTS 55 1,674,370 Methlin --------------- June 19, 1928 1,808,847 Hatcher ----------- ---- June 9, 1931 2,047,596 Romberg -------------- July 14, 1936 21101,086 Moore ----------------- Dec. 7, 1937 2 388 670 Bixby 60 ----------------- Nov. 13, 1945 2:397,501 -Meyer ----------------- Apr. 2, 1946 2,415,413 Burgess ------ I -------- Feb. I 11 1947 2,453,977 Eames ----------------- Nov. 16, 1948

2 1 9 7 4 @ 5 6 9 Uil-i'ted States Patent,Office Patented Mar. 14, 1961 2,974,569 AAMUNITION FEED MECHANISM 5 G,arrett P. S. Cross, Beverly, Mass., assignor to United Shoe Machinery Corporation, Flemington, N.J., a corporation of New Jersey Filed Sept. 2, 1947, Ser. No. 771,677 10 1 Claim. (Cl. 89-33) The invention relates to an automatic ammunition feed 15 mechanism of the type used on aircraft guns, the feed mechanism being supplied with cartridges from a linked belt. It is an object of the present invention to provide an ainmunition feed mochanisrq of this type with iinproved 20 means for horizontally feeding the belt e., to the gun, i. into -osition above the mouth of the feed - mechanism from where successive cartridges are stripped from the belt and moved down into position in the path of the breech bolt of the gun. 25 In accordance with a feature of the invention, a reciprocating horizontal feed member or pusher is moved into position to feed the belt by means energized by the recoil of the gun, and a link support which facilitates the stripping operation is so controlled by the belt feed mem30 ber that it does not interfere with the feed movernent of the belt. This and other features of the invention will be apparent from the following detafted description and will b-. pointed out in the claim. 35 In the drawings, Fig. I is an angular top view of the feed mechanism, the cover of which has been removed; Fig. 2 is a vertical sectional view of the feed mechanism; 40 l,'i g. 3 is a section on the line III-III of Fig. 2; Fig. 4 is a section on the line IV-IV of Fig. 2; Fig. 5 is a section on the line V-V of Fig. 2; and Fig. 6 is a detail view of a link support for facilitating stripping of the cartridges frorn their belt. 45 The invention is shown as embodied in a feed mech@.nisir. for provid;ng a 20 mm. aircraft gun with ammunitic,n and is par-ticularly concerned with the horizontal feed tinit of a feed mechanism of the type disclosed in an application for United States Letters Patent filed in the 50 rame of Charles K. Woodman under Serial No. 674,542 o,@i June 5, 1946. The feed mechanism is contained in a housing 10 (1- igs. 1. and 2) adapted to be rnounted on a gun G a portion Of m,hicli is shown in Fig. 3. The horizontal feed unit of the 55 mechanism brings successive cartridges, which are supplied to the feed me--hanism by means of a belt, tbrough a chute 12 formed in a cover 14 which is detachably secured to the housin- 10 and moves the cartridges into a position above a mo@uth 16 of the feed mechanism. The 60 cartridges, successively moved into position above the feeder mouth, are stripped from the belt, and moved downward into position to be picked up by the breech bolt of the gun, by stripper and vertical feed mechanisms (5, 5 (not shown) which are fully described in the - aforementioned application. A horizontal feed movement is imparted to the cartridges by a feed member or pusher 18 (Fig. 1) which has ears 19 rotatably mounted on a pin 20 (Fig. 3). The 70 pin 20 at its outer ends carries rolls 22 (Fig. 1) which move in hor'zontal guideways 24 in the housing 10. 2 Projections on the pusher are normally held in an upwardly inclined position (see Fig. 3), to engage the rear faces of successive cartridges, by means of a plunger 26 seated in a housing 28 formed on a link 30, a spring 32 normally urging the plunger into engagement with a face on the pusher 18. The extent of upward movement of the pusher 18 about the axis of the pin 20 is limited by engagement of the left ear 19 (Fig. 1 ) with the toD of the plunger housing 28. The link 30 is also motinted on the pin 20 and is pivota'@.y connected to a double-armed feed lever 34. The I.-ver 34 is mounted to oscillate about a shaft 36 (Fig. 2) and serves to impart feed movements to the pusher 18. The shaft 36 is rotatably mounted in bearings of the housing 10 and extends through a cylindrical extension of the housing. The energy or force for imparting feed niovement to the pusher IS is derived from a torsion sprin.- 38 which is energized by the recoil movement of the .-un. Tl,-. sprin- 38 surrounds a spacer 40 on the shaft 36. One end @f the spring is secured to a hub of - the feed lever 34 and the other end of the spring is jo-',ned to an anchor 42. The anchor 42 is rotatably moiinted on the right hand end (Fig. 2) of the shaft 36 aiid extci3ds partially within a sleeve 44 forming the end of the cylindrical extension of the housing 10. Lon.-itudinal movement of the anchor 42 relatively to the shaft 36 is prevented by a retai-iiing member 46 (Fi_a. 4) which is pivoted to the anchor 42 and is moved into en-aget-nent with an annular groove in the shaft by a sprin- 48. The anchor 42 is nornially held locked against rotary novement by a non-rotary toothed rin@ 50 (Fig. 2) engagin- a ratchet 52 inte,aral with the anchor 42. The rin@ 50 is mounted within the sleeve 44 and is movable longitudinally thereof along the inner face of the sleeie. A sprin- 54 tends normally to hold the ring 50 in lockinengagement with the ratch@-t 52 and to hold the spring 38 under preliminary tension. The tensio@.i of said spfing 38 may be varied by rotation of the anchor 42. The spring 38 is energized and the pusher 13 is retracted from the feeder mouth from the position it assumes at the end of its feed movement into the position it assumes at the beginning of its feed movement by a cam lever 56 (Figs. 1, 2, and 3) secured to the shaft 36 between the arms of the feed lever 34. Pivoted to the bifurcated upper end of the lever 56 is a hook 53 which is yieldingly held in engagement with a pin 60 on the lever 34 by a springpressed plunger 62 (Fig. 3). At its iniier side the Jever 56 carries a cam roll 64 engaged by a cam 66. The cam 66 is mounted on an arm @68 secured to a shaft 70. The shaft 70 is carried by a rear bracket 72 and a forward bracket (not shown) attached to the breech casing of the gun G, the casing reciprocating with the moving gun parts. The lever 56 is actuated by the cam 66 upon movemeiit of the gun iii recoil to swing outward, i.e., in a clockwise directioii (Fi,. 3) swinging the lever 34 correspondingly about the axis of the shaft 36 to n-iove the pusher IS outward into posit@'.On to assume feed control over another carlrid@e. This clockwise movement of the lever 34 serves @simultaneously to energize ille spring 38. 'nie feed lever 34 is swun- in a clockwise direction until a projection 74 on the hook 58 en-ages a release plate 76. The plate 76 is pivotally joined to the housing 10 by a pin 78 and is lield in operative position by a sprin- 80 riounted on the pin. Enga,@emeiit of the projection 74 with the plate swings the hook 58 out of engagement with the pin 60, whereupon the released feed lever 34 is swung in the opposite direction by the spring 38 imparting a feed movement to the pusher 18 through the link 30. The plate 76 may be swung into an inoperative position about its pivot 78 to permit certain adjustments of