US2367488A

US2367488A - Automatic firearm

Info

Publication number: US2367488A
Application number: US364351A
Authority: US
Inventors: Dobremysl Josef
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-11-08
Filing date: 1940-11-05
Publication date: 1945-01-16
Anticipated expiration: 1962-01-16

Description

J. DOBREMYSL Jn. is, 1945.

AUTOMATIC FIREARM Filed Nov. 5, 1940 4 Sheets-Sheet 1 frz van for.'

JOSEF .003@ fwn/.s1

Jann E6, 1 DOBREMYSL 2,367,488

AUTOMATIC FIREARM Filed Nov. 5, 1940 4 Sheets-Sheet 2 In ve nior JUSEFOB/EE/VYSL @gg-fg Jan. 16, 1945. J DOBREMYSL 2,367,488

AUTOMATIC FIREARM Filed Nov. 5, 1940 4 sheets-sheet 3 Y -FIG.4.

Inveniar" Jan. 16, 1945.

J. DoBREMYsL. 2,367,488

AUTOMATIC FIREARM Filed Nov. 5, 1940 4 sheets-sheet 4 F IG.7.

@Ei i X wx i Y 54 5S se so 57 fn ven for l .70.55F llos/'MM L Patented Jan. 16, 19.45

Urrea sTA'rlazsA PATENT oFFIcE Application November 5, 1940, Serial No. 364,351

in Great Britain November 8, 1939 2 claims. l (o1. ssa- 33) .The object of the invention is to provide a feed operating mechanism for guns of the types referred to which shall be reliable in operation,

of a simple and. robustl construction and of a comparatively light. weight which does not appreciably increase with the calibre of the Weapon.

The present invention relates to guns of the type in which the movement of the feed mechanism is derived from the kinetic energy of the recoiling breech mechanism and the main feature of the present invention comprises an arrangement according to which the kinetic energy of the breech mechanism is transmitted to the feeding mechanism -by means of a member capable of a rocking motion.

In a preferred embodiment ofthe invention the kinetic energy of the breech mechanism during the later stage of its recoil movement is transmitted to the'feed mechanism by means of a rocking lever.

The rocking movement of the lever is transmitted to the carriage of the feed mechanism by means of a crank arm and link.

According to a further feature of the invention the active part of the breech mechanism is shaped so thatyvhen the rear end thereof engages the rear arm of the rocking lever the fore arm of the lever simultaneously engages the shaped edge or surface of the breech mechanism. y

The arrangement is such that the lever is` positively guided on the breech mechanism at two points on either side'of its pivot so that any sudden'impact movement is avoided.

The upperV side of the fore arm of the lever may co-operate withthe cover or with any other part of the lire arm,to limit the rocking movement of the lever. A spring may be arranged to return the lever into its initial position.

It is an important advantage of the invention, that it allows the feeding of the cartridge belt from either sideY of the iire arm.` For this purpose guiding means for the transmitting rod are arranged at each side of the arm, so that by inserting the rod into the'respective guide the device may be used for feeding the cartridge belt .from either side'of the arm.

Two embodiments of the invention are shown by way of example in the accompanying drawings.

Fig. l is a vlongitudinal section through the central part of the gun. Y

Fig. 3 is a plan View of the central part of the gun as illustrated in Fig. 1 with the'cover of the feed box removed and with retracted transmitting link of the gun.

Fig. 4 is a sectional View along the line IV--IV of Fig. l.

Fig. 5 is a longitudinal section through the central part of the gun in the position the gun parts occupy during the recoil movement.

Fig. 6 is a longitudinal section through the central part of the gun in the position the gun parts occupy during the return movement.

Fig. '7 is a longitudinalsection through the central part of another type of the gun as illustrated in the Figs. 1-6.

Fig. 8 is a longitudin-al section throughthe central part of the gun type illustrated in Fig. 7 but in another position of the relevant gun parts.

In the embodiment of theA invention, shown in Figs. 1-6, the gun is of thegas operated type. The lbarrel I is provided at a suitable point on its length with a channel (not shown) through which gases from the barrel may enter a gas cylinder and operate a piston, mounted therein -for to and fro movement. Such an arrangement is Well known and need not be described in detail.

A piston rod 2 is connected or made integral 'at one end with the piston, the other end being connected or made integral with a breech block carrier 3. A recoil spring 4, housed in the lbutt 5 acts upon the carrier 3 by the intermediary of a rod 6, urging the carrier 3 and the parts connected therewith in forward direction. A breech block 'l of the tilting type is arranged for co-operation With the carrier 3. In the position shown in Fig. 1 the breech block 1, having the cartridge 8 into the barrel chamber, has been raised by the carrier 3 into a position wherein the rear surface 'la of the breech block 1 is locked against a locking shoulder 9.

A firing pin lll is housed in the breech block; the firing pin is adapted to be struck by the carrier 3 in the last part of its forward movement to re the cartridge.

The breech block comprises further an ex-v tractor II held in proper position by a spring loaded plunger I2.

An .ejector i3 is mounted in the casing of the gun and is adapted for engagement with empty cartridge cases, drawn back by the extractor, to eject the spent cartridge cases out of the gun.

The trigger mechanism of the gun consists of a scar I4 capable of engaging a corresponding notch I in the carrier 3 and retaining the latter in retracted position. The sear may be actuated by 4a, link i6 operated by a trigger lever` I1, which is mounted rotatably on a pivot I8. If the trigger lever i1 is pulled, the link I6 engages the lower arm of the sear and swings its upper arm out of engagement with the carrier 3, freeing it for movement under the influence of the recoil spring 4.

In the rear part of the casing I3 of the gun a lever 2i) is rigidly secured between its ends on a shaft 2| (see Fig. 4). In normal position the rear arm 23a of the lever 2U, lies in path of the rear surface 1a. of the breech block 1 as' shown in Fig. l. A spring 22 may be used to ensure that the lever 20 is kept in this position or returned to it after being rocked out, as will be described hereinafter. This spring, however, is not essential. The fore arm 2Gb of the lever 28 is adapted to yco-operate with a. rib or shaped surface 23, Fig. 6 on the breech block 1, as will be more fully explained with reference to Figs. 5 and 6.

The shaft 2l is connected or made integral with a crank arm 24, the latter being provided with a slot 25 for co-operation with a projection 25 on a transmitting link 21. The link 21 is mounted for longitudinal movement in suitable guides on the casing of the gun (see Fig. e). The guides are preferably arranged on both sides of the gun to make possible the use of right or left hand feed of cartridges.

The link 21 is provided at its fore end with a stone 28 (see Figs. 2 and 3).

A feed box is mounted on the central part of the gun, said feed box comprising a casing 2S with suitable guiding means for the cartridge belt 30, i. e. enlarged mouth 3| for receiving the full cartridge belt and a guide 32 for guiding the empty cartridge belt out of the gun. A feed carriage 33 (Fig. 2) is mounted for to and fro movement in transverse direction in the casing 29 of the feed box. A feeding pawl 34 is carried by the carriage 33, said pawl serving to push the cartridge belt through one feeding step upon feeding movement of the feed carriage. The feed box is closed by a cover 35 carrying the retaining pawl 36 which retains the cartridge belt in position.

The feed carriage 33 is provided on its lower surface with a cam groove 31 (see Fig. 3), adapted to co-operate with the stone 28, of the link 21, in such a way, that if the stone moves rearwardly, in the direction of the arrow A the carriage 33 moves in the direction of the arrow B, Fig. 3.

The device operates as follows:

After the shot has been fired the carrier 3 moves backwards under the influence of the gas pressure acting on the piston. During this movement the rear part 38 of the carrier releases the rear transverse 39 on the breech block for downward movement and during further backward movement of the carrier 3 its inclined face 68 engages the transverse 39 and tilts the breech block out of engagement with the locking shoulder 9. The breech block gets embedded into the inner space of the carrier (see Figs. 5 and 6) and moves back with the carrier 3 as one unit. During this further movement the rear upper surface 1a of the breech block abuts the curved rear part of the lever 20 which is thus rocked in the direction of the arrow C in Fig. 5. This movement is transmitted by the intermediary of the shaft 2| and crank arm 24 to the link 21 which is thereby moved in rearward direction (direction of arrow D in Fig. 5). The stone 28 (Fig. 3) being integral with the link 21 takes part in this movement and by the intermediary of the inclined or cam groove 31 imparts to the feeding carriage a transverse movement in the direction of the arrow B in Fig. 3. The feeding pawl 34, which at the beginning of this movement has been in engagement with that cartridge in the belt which had to the brought next into feeding position, has during this movement shifted this cartridge into register with the breech block 1, as shown in Fig. 3. The belt is Yretained in this position by the re'- taining pawl 36.

During a part of the recoil movement of theV breech block when the rear arm 20a of the lever 20 is in engagement with the rear surface 1a of the breech block, the fore arm 2Gb of the lever 20 engages simultaneously the surface or rib 23 on the breech block, as is shown in Fig. 5. In this manner a controlled guiding of the lever 2li at two :points on'either side of the axis of rotation of the lever 2U is obtained, so that the lever 20 is positively guided and a uniform movement ensured.

Upon the return movement of the carrierbreech block unit the rear upper part 1b of the breech block engages the forearm 20h of the lever 20 and swings the latter back into its original position (arrow E in Fig. 6). This movement is transmitted by the shaft 2l, crank 24 to the link 21 and stone 28, which move in the direction of arrow F in Fig. 6. The stone 28 moving in the cam groove 31 imparts to the feed carriage a movement in the direction from left to right in Figs. 2 and 3. The feeding pawl, moving together with the carriage 33 slides under the next cartridge to the right and springs behind this cartridge, prepared for a new feeding step.

The upper part of the fore arm 20h of the lever 20 is preferably made as an abutment cooperating with the upper surface of the casing I9 (see Fig. l) to limit the movement of the lever 20.

Figs. '1 and 8 show the invention as used in connection with another type of gun of the tilting breech block class. In this gun the movement of the breech mechanism is derived from the recoil of the gun instead of the gas pressure.

The breech mechanism itself and the whole feed mechanism are similar to those of the previous example so that no detail reference need be made to these parts.

The gun mechanism asl a whole is mounted for a short recoil movement in a guide arranged on the mounting 50 of the gun. The barrel 5l is connected with a sleeve 52 carrying a pivot 53 on which an accelerating lever 54 is mounted for rocking movement. The mounting 50 of the gun is provided with a projection 55 extending into the xpath of the lower arm of the lever 54. The upper arm of the lever 54 is adapted to engage the fore end of the ca'rrier 56.` The latter is biased by a recoil spring 51 and adapted to co-operate with a breech block 58 in the same manner as has been described in connection with the first example.

Fig. 7 shows the mechanism of the gun in a position in the moment of firing the cartridge 59. In this position the lever 54 is clear of the proection 55. The breech block is in locked posiion.,

Fig. 8 shows the'parts of the gun in a position shortly after the recoil movement of the mechanism has started.

The barrel 50 together with the accelerating lever 59 and other mechanisms move back under the inuence of recoil forces. After a short rearward movement the lower arm of the accelerating lever 59 strikes against the projection 55 and is rocked by the latter in clockwise direction (see Fig. 8). The upper arm of the lever 54 engages with the front face of the carrier 56 and imparts to the latter an impulse in rearward direction so that from this moment the carrier begins to move faster than the barrel. The latter returns then to its fore position and the carrier continues its rearward movement during which it unlocks the breech block, as has been previously described, and moves back together with the latter. During this movement the upper surface of the breech block 58 comes into engagement with the lever 59 which is similar to the lever 2D of the first example, and actuates the lever 59 in the same manner as has already been described.

It is a particular advantage of the invention that the device may be easily arranged for feeding from either side. For this. purpose a guide 60 is arranged also on the right hand side of the gun, see Fig. 4, and to change from one side to the other it is only necessary to insert a transmitting link, which is symmetrical to the link 21,

into the guide 60 and to set the crank arm 2|-24 30 accordingly, as shown in dotted lines in Fig. 4. The guides may be arranged either outside or inside the body of the gun.

I claim:

1. A device for operating the cartridge belt feed mechanism of machine guns comprising a casing, a belt feed carriage, a breech block having a steering portion on its surface, a rocking member with a shaft having a part engaged for sliding engagement with said steering portion of the breech block, a crank on the shaftv of the rocking member, a link connected with said crank by connecting members capable of transforming the swinging movement of the rocking member into a rectilinear movement of said link, a guide on oneside of said casing in which said link is mounted for longitudinal movement and a second guide on the other side of said casing, in which the said link may be mounted to slide also 'in longitudinal directions, and means on said link for operating the cartridge belt feed mechanism.

2. A device for operating the cartridge belt feed mechanism of machine guns comprising a casing, a belt feed carriage, a breech block, having steering ribs on its surface, a rocking lever with a shaft and two arms each having a part adapted to slidably engage one of said steering ribs of said breech block, a crank on the shaft of the rocking lever provided with a slot, a link having a bolt fitting in said slot of the rocking lever in such a manner that the swinging movement of the rocking lever is transformed in a 'rectilinear movement of said link, a guide for said link on said casing in which said link is capable of sliding in longitudinal direction, and means on said link for operating the cartridge belt feed mechanism.

JosEF DoBREMYsL.