Title:
Firearm
United States Patent 2331347


Abstract:
The present invention relates to improvements in those semi-automatic or wholly automatic fire arms. One object of the invention is to produce an automatic rifle or the like, in which a gas nozzle is mounted slidably on the free end of the barrel in such a manner that the bullet, after having...



Inventors:
Erik, Rehnberg Per Harry
Application Number:
US26697639A
Publication Date:
10/12/1943
Filing Date:
04/10/1939
Assignee:
SNABB AV AR 1938 AB
Primary Class:
International Classes:
F41A3/48; F41A5/18; F41A5/20; F41A9/26; F41A19/30; F41A19/31
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Description:

The present invention relates to improvements in those semi-automatic or wholly automatic fire arms. One object of the invention is to produce an automatic rifle or the like, in which a gas nozzle is mounted slidably on the free end of the barrel in such a manner that the bullet, after having left the barrel, has to traverse only a very short distance within the gas nozzle.

A further object of the invention is to provide an automatic fire arm in which the elements which serve to reciprocate the breach block mechanism and their associated springs are mounted in a compact manner within one another.

A still further object of the invention is to provide an automatic fire arm in which the breech block driving mechanism is of simple construction and consists of a limited number of sturdy elements which offer a high resistance to wear and tear. Still another object of the invention is to produce an automatic fire arm with a breech block driving mechanism, the parts of which can be easily dismounted, cleaned and exchanged.

According to the invention, these and other objects are accomplished by the arrangement and combination of parts set forth in the following detailed description, defined in the appended claims and illustratively exemplified in the accompanying drawings, in which: Figs. 1 and la are to be taken as a single figure and constitute a longitudinal section through a rifle, according to the invention, with the movable parts in the position they assume immediately after firing. Figs. 2 and 2a, taken together, are a similar longitudinal section through the rifle with the movable parts in their rear end position, and Fig. 3 is a longitudinal section through the rear portion, of a modified embodiment. In the drawings, the numeral I indicates the rifle stock on which is mounted the breech member 2 with the barrel 3, the said barrel being as usual provided with backsight 4 and foresight 5.

Around the free end of the barrel 3 is mounted a hollow cylindrical nozzle 6, into the front end of which there is screwed an end piece 8 provided with a central opening 7. The muzzle of the barrel 3 is conically bored. To the underside of the nozzle 6 is welded a U-shaped sleeve 9 which by means of a bayonet-joint 9a is connected with a cylindrical member 10 which is open at the top of its front portion. A rack 12 having teeth II is secured to the nozzle within the sleeve 9. The rack 12 is arranged resiliently in such a way that its rear end 13 is urged somewhat away from the nozzle 6. However, this end 13 is wedge-shaped and enters, in its rear position, a cam groove 14 in a bearing 15 secured to the barrel. Surrounding the cylindrical member 10 and resting with one end on a ring 16 secured to the member 10 and with the other end of the bearing 15 there is mounted a helical spring 17 which is arranged as a pressure spring.

A spindle 18 which extends through the cylindrical member 10 and is guided for slidable movement therein, is provided at its front end with teeth 19 which cooperate with the teeth II on the rack 12. At its rear end the cylindrical member 10 is provided with a nut 20 cooperating with a buffer 20a which reduces the shock when the nozzle 6 is flung forward. Within the member 10 and resting against the nut 20 and a guide shoulder 21 on the spindle 18 there is provided another helical spring 22 arranged as a pressure spring. The spindle 18 traverses the nut 20 and is at its rear end slidably connected with a cross piece 24, in which is provided a smaller buffer spring 24a and to which are secured two rails 25, only part of the right one of said rails being shown in the drawings. The said rails 25 extend backward on both sides of the magazine 26, and are at their rear end detachably connected with a reciprocable breech block mechanism of any known type. A suitable breech block mechanism is described, for instance, in the British Patent No. 131,350.

The construction of the breech block mechanism does not form part of the present invention, but, for the sake of completeness, its principal elements may be briefly outlined as follows: The rear ends of the rails 25 are connected with an approximately semi-cylindrical member 27. In said member is provided a screw thread 28 which is engaged by a correspondingly screw threaded projection 30 on the rear portion of the breech block 29. The breech block is provided with lugs 31 in the usual way in Mauser rifles, said lugs cooperating with lugs 32 in the breech member 2. The lugs 31 are provided with projecting fingers 33 which serve to withdraw the cartridge shell from the breech member. The block 29 may be actuated by means of a knob 34, the arm 35 of which has been shortened a little and curved to the right side of the rifle. The striker with lug is indicated by 36. The striker glides on a guide rail 37, which is elongated backward in order to be stable. The striker 36 cooperates with a corresponding lug 40 located on the sear lever 39 connected with the trigger 38, the said lug 4 retaining the striker 36 when the trigger 38 1 in its front position. On that end of the sea lever 39 which is opposite the lug 40 there i located a pin 41 which enters a correspondini recess 42 in the block 29 when the block ha& been closed and the trigger has been pushe( backward.

The modes of operation is as follows: Immediately after firing the parts assume their position. shown in Figs. 1 and la. The cartridge shell 4S still lies in the firing position. The nozzle 6 has been pressed forward by the gases behind the bullet, and the teeth I I of the rack 12 have engaged the teeth 19 on the spindle 18. During this procedure the spring 17 has been compressed and now tends to move the cylindrical member 10 and the elements connected therewith backward. However, in order to open the bolt 29 it is necessary to turn the same, and, as the pin 41 is still in the recess 42 and prevents this turning, the elements will remain in their positions until the trigger 38 has been released. When this has taken place, the semi-cylindrical part 27 is pressed backward by the rails 25. At the beginning of this movement the screw threaded projection 30 on the block 29 will glide in the screw thread 28 and thus turn the block a quarter of a revolution in order to release the lugs 31. At continued pressure of the spring IT the breech block 29 will be withdrawn to the position shown in Fig. 2, the empty cartridgeshell being thrown out in the usual manner.

However, at the end of the rearward stroke of the nozzle, the end 13 of the resilient rack 12 enters the cam groove 14 in the bearing 15, whereby the teeth II are lifted off the teeth 19 of spindle 18. Spindle 18 is thus released and continues to move rearwardly a short distance.

The spring 22, which has been previously compressed, now presses the breech block 29 forward again. During this procedure a loaded cartridge 44 is introduced in a known way to the firing position and the breech block is locked again in its inner position. The engagement of the end 13 of the rod 12 in the cam groove 14 allows the teeth 19 to pass forwardly of the teeth II. The elements now reassume the position shown in Fig. 1 except the nozzle 6, the elements rigidly connected with the same, the trigger 38, the lever 39 and the striker which assume the positions shown in Fig. 2. When the trigger 38 has been pressed backward again the new cartridge introduced to the firing position is fired and the process is repeated.

In order to make the gun still more safe, there may be provided a protective cap above the rear part of the breech block and extending to the end of the path of movement of the breech block, as shown in Fig. 3. C When a protective cap is used it is not necessary to retain the breech block in its rear position, and therefore the members intended herefor may be omitted. Moreover, by a simple change of the firing mechanism the gun may be 0 made wholly automatic or wholly and semiautomatic.

It is evident that the device may be varied in many respects within the scope of the invention.

Having now described by invention, what I 7 claim as new and desire to secure by Letters Patent is: 1. In an automatic fire arm, the combination with a barrel, having a conically bored muzzle, and a reciprocable breech block mechanism, of a 7ý 0 gas nozzle slidable on and surrounding the free s end of the barrel, said nozzle including a front r wall provided with a central opening in register s with the barrel bore, said front wall, in the rear g 5 end position of said nozzle, being disposed dis rectly adjacent said muzzle, a first elongated elei ment slidable along said barrel and rigid with said nozzle, a spring acting on said barrel and first element, respectively, to urge the latter into S10 its rearmost position, a second elongated element mounted for longitudinal movement through said first element and periodically slidable in unison with and relative to said first element, a latch arranged for longitudinal movement with one of said elements, said latch projecting yieldingly into the path of the other element, means on said other element for cooperation with said latch to lock the two elements together during the rearward stroke of the nozzle while allowing independent longitudinal movement of the first element during the forward stroke of the nozzle, means connecting the rear end of said second element with said breech block mechanism, means on said barrel to disengage said latch from said cooperating means at the end of the rearward stroke of the nozzle, and spring means between the first and second elements to displace said second element in forward direction independently of said first element when said latch has been disengaged from said cooperating means.

2. In an automatic fire arm, the combination with a barrel, having a conically bored muzzle, and a reciprocable breech block mechanism, of a gas nozzle slidable on and surrounding the free end of the barrel, said nozzle including a front wall provided with a central opening in register with the barrel bore, said front wall, in the rear end position of said nozzle, being disposed directly adjacent said muzzle, a first elongated element comprising a hollow cylindrical member slidable along said barrel and rigid with said nozzle, a pressure coil spring surrounding said cylindrical member and acting on said d5 member and on the barrel, respectively, to urge the nozzle into its rearmost position, a second elongated element comprising a spindle slidably guided in said cylindrical member, a pressure 5coil spring surrounding said spindle within said Scylindrical member and acting on said two elements to urge said spindle forward relative to said cylindrical member, a latch arranged for longitudinal movement with one of said elongated elements, said latch, projecting yiedingly into the path of the other elongated element, means on said other element for cooperation with said latch to lock the two elements together during the rearward stroke of the nozzle while allowing independent longitudinal movement of ;0 the cylindrical member and nozzle during the forward stroke of the latter, means connecting the rear end of said spindle with said breech block mechanism, and means on said barrel to disengage said latch from said cooperating means 5 at the end of the rearward stroke of the nozzle.

3. An automatic fire arm, as claimed in claim 2, in which said latch is arranged for movement with said cylindrical member and comprises a resilient rack having at its free rear end a toothed 0 portion and a wedge-shaped thorn, said cooperating means including a corresponding rack portion on said spindle, and said latch disengaging means including a bearing provided with a cam groove into which said thorn of the resilient rack 5 enters at the end of the rearward stroke of the nozzle to disengage the toothed portion of the resilient rack from the rack portion of the spindle.

4. In an automatic fire arm, the combination with a barrel, and a reciprocable breech block mechanism, of an elongated hollow element slidable longitudinally along said barrel, said first element having a nozzle in line with the free end of the barrel, a spring acting on said barrel and said first element respectively to urge the latter into its rearmost position, a second elongated element mounted for longitudinal movement through said first element and periodically slidable in unison with and relative to said first element, a latch carried on said first named element and projecting yieldingly into the path of the second element, means on said second element for cooperation with said latch to lock the two elements together during the rearward stroke of the first named element while allowing independent longitudinal movement of the first element during the forward stroke of the latter, means connecting said second element with said breech block mechanism, means to disengage said latch from said cooperating means at the end of the rearward stroke of the first element, and spring means between the first and second elements compressible during rearward movement of said second element for displacing the second element in forward direction independently of said first element when the latch has been disengaged.

PER HARRY ERIK REHNBERG.