LOW RECOIL FIREARM

Abstract

A low recoil firearm 1 provided with counterweights 22, the number of counterweights 22a, 22b is two or more, and a kinetic energy of the bullet received by a barrel 11 is transferred and distributed to the counterweights 22a, 22b. A stop mechanism separately stops the counterweights 22a, 22b from each other. Although the kinetic energy transmitted to one counterweight is eliminated in the conventional technology, the kinetic energy distributed to two counterweights 22a, 22b is eliminated in the present invention.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent specification is based on Japanese patent application, No. 2022-0133912 filed on Aug. 21, 2023 in the Japan Patent Office, the entire contents of which are incorporated by reference herein.

PRIOR ART

[Patent Document 1] Japanese unexamined patent application publication No. 2017-129306

BACKGROUND OF THE INVENTION

The present invention relates to a low recoil firearm. In particular, the present invention relates to a low recoil firearm provided with counterweights.

In firearms such as a gun, recoil is caused when shooting a bullet. The gun having a counterweight for reducing the recoil is known. In a low recoil firearm shown in Patent Document 1, the recoil is reduced by transmitting the recoil of a barrel to the counterweight when the bullet is shot.

SUMMARY OF THE INVENTION

When the bullet is shot, a kinetic energy of the bullet received by the barrel is transmitted to the counterweight. However, the kinetic energy received by the counterweight should be eliminated. It cannot be said that the process of eliminating the kinetic energy received by the counterweight in the conventional low recoil firearm is optimum.

The present invention further reduces the recoil of the low recoil firearm having the counterweight.

The present information relates to a low recoil firearm provided with counterweights, the number of the counterweights is two or more, and a stop mechanism for separately stopping each of the counterweights is provided.

In the above described configuration, the number of the counterweights is two or more, the kinetic energy of the bullet received by the barrel is transferred and distributed to each of the counterweights. The stop mechanism separately stops each of the counterweights. Although the kinetic energy transmitted to one counterweight is eliminated in the conventional technology, the kinetic energy distributed to two counterweights 22a, 22b is eliminated in the present invention.

Since the kinetic energy distributed to a plurality of counterweights is eliminated in the low recoil firearm of the present invention, the recoil can be further reduced compared to the firearm provided with a single counterweight.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of an initial state of a low recoil firearm concerning an embodiment of the present invention.

FIG. 2 is a schematic diagram of an intermediate state of the low recoil firearm of the embodiment.

FIG. 3 is a schematic diagram of a stopped state of the low recoil firearm of the embodiment.

FIG. 4 is a schematic diagram of the initial state simply for showing an operation principle of the low recoil firearm of the embodiment.

FIG. 5 is a schematic diagram of the stopped state for simply showing the operation principle of the low recoil firearm of the embodiment.

FIG. 6 is a front view of a counterweight for simply showing the operation principle of the low recoil firearm of the embodiment.

FIG. 7 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 8 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 9 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 10 is a schematic diagram of an intermediate state of the low recoil firearm of the modified example.

FIG. 11 is a schematic diagram of an intermediate state of the low recoil firearm of the modified example.

FIG. 12 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 13 is a schematic diagram of the intermediate state of the low recoil firearm of the modified example.

FIG. 14 is a schematic diagram of the stopped state of the low recoil firearm of the modified example.

FIG. 15 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 16 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 17 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 18 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 19 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 20 is a schematic diagram of the stopped state of the low recoil firearm of the modified example.

FIG. 21 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 22 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

FIG. 23 is a schematic diagram of the stopped state of the low recoil firearm of the modified example.

DETAILED DESCRIPTION OF THE INVENTION

Hereafter, embodiments of the present invention will be explained based on the drawings.

FIG. 1 to FIG. 3 show a low recoil firearm of an embodiment of the present invention by a schematic diagram. FIG. 1 shows an initial state, FIG. 2 shows an intermediate state and FIG. 3 shows a stopped state.

In the drawings, a low recoil firearm 1 is the low recoil firearm provided with counterweights. A shooting port is provided on a barrel 11 of the low recoil firearm 1 at the right side in the drawings. The direction of opening the shooting port is called the front direction, while the direction toward the cartridge chamber is called the rear direction. The barrel 11 is supported by a part 12 of a frame so as to be movable in the front-rear direction. When a bullet is shot (fired), the barrel 11 is configured to receive a recoil (reaction) leftward in the drawings.

A slide rail 21 is arranged on a rear of the barrel 11 and counterweights 22 (22a, 22b) are supported by the slide rail 21 so that the counterweights 22 are slidable in the front-rear direction within a predetermined range. Note that a bolt 13 is arranged on a rear of the barrel 11. In addition, FIG. 4 to FIG. 6 simply show the operation principle by a schematic diagram. FIG. 4 shows the initial state and FIG. 5 shows the stopped state. FIG. 6 shows the counterweight by a front view. For simply showing the configuration, the shape of the counterweight is simplified.

The counterweights 22a, 22b are the members identical to each other and vertically reversed in the attached state. The slide rail 21 includes a planar portion 21a. The slide rail 21 is fixed to a not-illustrated frame or the like at an upper part of the planar portion 21a. A columnar portion 21b having a circular cross-section is formed on a lower end of the planar portion 21a.

The counterweights 22 (22a, 22b) has a rectangular column shape as a whole. A groove 22c recessed inward is formed on the upper surface and the lower surface of the counterweights 22 in the center of the width direction so that the planar portion 21a of the slide rail 21 is inserted into the groove 22c. A circular recessed portion 22d is formed in the inner part of the groove 22c so that the columnar portion 21b of the slide rail 21 can be inserted into the circular recessed portion 22d. The width of the groove 22c is smaller than the diameter of the columnar portion 21b. The length of the groove 22c is slightly shorter than the length of the planar portion 21a. Therefore, the slide rail 21 can be inserted into the counterweights 22a, 22b in the front-rear direction. When the slide rail 21 is inserted into the counterweights 22a, 22b, the slide rail 21 can suspend and support the counterweights 22 (22a, 22b) in a state of being slidable in the length direction.

Through holes 22e, 22e are penetrated through the counterweights 22 in the front-rear direction at a left and a right symmetrical position. The through holes 22e are formed by a large diameter portion 22e1 having a large diameter located at the rear side and a small diameter portion 22e2 having a smaller diameter located at the front side. A bolt 23 is inserted into each of the through holes 22e from the rear side. A head portion 23a of the bolt 23 is inserted into the boundary surface between the small diameter portion 22e2 and the large diameter portion 22e1. Only a screw portion 23b penetrates through the small diameter portion 22e2.

When the counterweight 22a and the counterweight 22b are arranged in the front-rear direction in a state that the up-down directions are reversed from each other, a female screw hole 22f is formed at a portion facing the small diameter portion 22e2 of the through holes 22e so that the screw portion 23b can be inserted into the female screw hole 22f. Therefore, the bolt 23 is inserted from the large diameter portion 22e1 and the screw portion 23b penetrating through the small diameter portion 22e2 and protruding from the small diameter portion 22e2 can be screwed into the female screw hole 22f.

In addition, a female screw hole 12f is formed on the part 12 of the frame in the similar position. Therefore, the screw portion 23b of the bolt 23 penetrating through the counterweight 22a adjacent to the barrel 11 can be screwed with the female screw hole 12f.

The length of the screw portion 23b is slightly longer than the length of the small diameter portion 22e2 of the through holes 22e. In the initial state, the counterweight 22a is located at the position abutting on the part 12 of the frame, and the counterweight 22b is located at the position abutting on the counterweight 22a. The counterweight 22b is stopped when the counterweight 22b is separated from the counterweight 22a for the length where the screw portion 23b is longer than the small diameter portion 22e2. The counterweight 22a is stopped when the counterweight 22a is separated from the part 12 of the frame for the same difference of the length.

As described above, the plurality of counterweights 22a, 22b are slidably connected with each other so that the plurality of counterweights 22a, 22b can be separated from each other by a predetermined distance in a moving direction. Accordingly, the stop mechanism is formed by the through holes 22e, the bolt 23, the female screw holes 22f, 12f and the like.

In the above described example, since the length of the bolt 23 is longer than the length of the small diameter portion 22e2, the counterweights 22a, 22b are moved from the state of being in contact with each other to the state of being separated from each other by a predetermined length. Directly, the counterweights 22a, 22b are stopped when the head portion 23a abuts on the boundary surface between the large diameter portion 22e1 and the small diameter portion 22e2. In this case, the counterweights 22 are stopped when the counterweights 22 collide with a stopper member formed by the bolt 23, the through holes 22e and the like.

On the other hand, it is not necessary to stop the counterweights 22 immediately after the head portion 23a abuts on the boundary surface between the large diameter portion 22e1 and the small diameter portion 22e2. For example, it is possible to make the head portion 23a of the bolt 23 slide on the inner surface of the large diameter portion 22e1 or interpose a sliding material between the head portion 23a and the inner surface so that a resistance is generated when the bolt 23 slides in the large diameter portion 22e1. In the above described case, the counterweights 22 are stopped by making the counterweights 22 slide on the stopper member formed by the bolt 23, the through holes 22e and the like.

It is also possible to make the counterweights 22 slide on the stopper member and then collide with the stopper member.

In the above described example, the counterweights 22a, 22b are connected with each other and the counterweights 22a, 22b are stopped by mutually acting with each other. It is also possible to provide a plurality of protrusions on the slide rail 21 at the positions where the counterweights 22a, 22b are stopped so that each of the counterweights 22a, 22b abuts on each of the protrusions when each of the counterweights 22a, 22b is moved rearward from the initial position. Namely, it is possible to make each of the counterweights 22a, 22b abut on each of the protrusions to independently stop each of the counterweights 22a, 22b instead of stopping the counterweights 22a, 22b by mutually acting with each other.

Returning to FIG. 1 to FIG. 3, FIG. 1 to FIG. 3 show the low recoil firearm concerning an embodiment of the present invention by a schematic diagram. FIG. 1 shows the initial state, FIG. 2 shows the intermediate state and FIG. 3 shows the stopped state.

As shown in FIG. 1, when the bullet is shot by the low recoil firearm 1, the barrel 11 receives the recoil and begins to move rearward. Because of this, the barrel 11 pushes the counterweight 22a with which a part of the barrel 11 is contacted rearward. At this time, the recoil of the barrel 11 is transferred to the counterweight 22a. Since the counterweight 22b is in contact with the counterweight 22a, the transferred kinetic energy is distributed to the counterweight 22a and the counterweight 22b. Then, the counterweight 22a and the counterweight 22b independently begin to move rearward by the recoil transferred respectively to each of the counterweight 22a and the counterweight 22b.

FIG. 2 shows the state where the counterweight 22a is separated from the part 12 of the frame by the above described length. Before the counterweight 22a reaches the above described position, the counterweight 22a is slid without receiving any restriction. However, when the counterweight 22a reaches the above described position, the head portion 23a of the bolt 23 abuts on the boundary surface between the large diameter portion 22e1 and the small diameter portion 22e2 of the through holes 22e. Thus, the counterweight 22a cannot move anymore and the counterweight 22a stops at the above described position. In other words, the first counterweight 22a in a plurality of counterweights 22 is stopped by the stop mechanism. Although the counterweight 22a pulls the part 12 of the frame rearward to stop the counterweight 22a, time difference occurs after the bullet is shot and the recoil is distributed. Consequently, the recoil is low.

On the other hand, the counterweight 22b, which receives the recoil separately from the counterweight 22a, continues to move rearward. FIG. 3 shows the state that the counterweight 22b is separated from the already stopped counterweight 22a by the above described length. Before the counterweight 22b reaches the above described position, the counterweight 22b is slid without receiving any restriction. However, when the counterweight 22b reaches the above described position, the head portion 23a of the bolt 23 abuts on the boundary surface between the large diameter portion 22e1 and the small diameter portion 22e2 of the through holes 22e. Thus, the counterweight 22b cannot move anymore and the counterweight 22b stops at the above described position. In other words, the second counterweight 22b in a plurality of counterweights 22 is stopped by the stop mechanism. Although the counterweight 22b pulls the counterweight 22a and the part 12 of the frame rearward to absorb the recoil, there is a time delay between the bullet being fired and the counterweights being stopped. As a result, the recoil is distributed and the recoil is minimized.

As described above, the number of the counterweights 22 is two or more and the stop mechanism formed by the through holes 22e, the bolt 23 and the female screw holes 22f, 12f is provided for separately stopping each of the counterweights 22 (22a, 22b).

In the low recoil firearm shown in FIG. 1 to FIG. 6, the weights of two counterweights 22a, 22b are equal. Namely, the weights of the plurality of counterweights are equal to each other. When the above described configuration is adopted, the kinetic energy of the recoil is approximately uniformly distributed.

FIG. 7 and FIG. 8 are schematic diagrams of the initial state of the low recoil firearm concerning a modified example.

In the modified example shown in FIG. 7, the weight of the counterweight 22a1 located nearer to the barrel 11 is greater than the weight of the counterweight 22b1 further from the barrel 11. In the modified example shown in FIG. 8, the weight of the counterweight 22a2 located nearer to the barrel 11 is smaller than the weight of the counterweight 22b2 further from the barrel 11. Namely, the weights of the plurality of counterweights are different from each other. Note that the part 12 of the frame is not illustrated and a barrel rear end 11a slidably supported at this portion is illustrated in the figures.

As described above, the recoil when the bullet is shot is transferred to the plurality of counterweights in the distributed state and the counterweights are stopped by the stop mechanism at a minute interval from each other. When the counterweights are stopped, the user of the low recoil firearm should receive the distributed recoil in some way. When the weight of the counterweight stopped first is greater or smaller than the weight of the counterweight stopped later, the manner of receiving the distributed recoil varies. Consequently, handlability of the low recoil firearm can be adjusted.

FIG. 9 to FIG. 11 show the low recoil firearm concerning a modified example by a schematic diagram. FIG. 9 shows the initial state, FIG. 10 shows the intermediate state and FIG. 11 shows the stopped state.

In this modified example, the weight of counterweights 22g1, 22g2 is greater than the weight of the counterweights 22a, 22b. Although not shown in the figures, a slide rail is provided and the stop mechanism similar to the modified example shown in FIG. 4 to FIG. 6 is provided.

As shown in FIG. 9, the counterweights 22g1, 22g2 are almost in contact with each other and slightly separated from the bolt 13 in the initial state.

As shown in FIG. 10, when the bullet is shot, the barrel 11 receives the recoil and retreats together with the bolt 13 located at the rear end. Thus, the bolt 13 located at the rear end abuts on the counterweight 22g1 located near the barrel 11. As a result, the counterweights 22g1, 22g2, which are almost in contact with each other, receive the recoil. Thus, the rearward-moving kinetic energy can be transferred. Accordingly, the counterweights 22g1, 22g2 begin to move rearward in a state of being almost in contact with each other.

FIG. 11 shows the stopped state. Before reaching the stopped state, two counterweights 22g1, 22g2 move rearward in a state of being almost in contact with each other and then the counterweight 22g1 stops first and the counterweight 22g2 stops after a short period of time. As shown in FIG. 11, the two counterweights 22g1, 22g2 are stopped with a time difference and located at the positions separated from each other.

Since the weight of the counterweights 22g1, 22g2 is large, greater recoil can be transferred to the counterweights. Consequently, the adjustment can be performed in accordance with the recoil, which varies depending of the bullet.

FIG. 12 to FIG. 14 show the low recoil firearm concerning a modified example by a schematic diagram. FIG. 12 shows the initial state, FIG. 13 shows the intermediate state and FIG. 14 shows the stopped state.

In this modified example, counterweights 22h1, 22h2 are formed in an approximately ring-shape to surround the bolt 13 by the counterweights 22h1, 22h2. Since the bolt 13 penetrates through the counterweights 22h1, 22h2, the slide rail is not required. In addition, the stop mechanism similar to the modified example shown in FIG. 4 to FIG. 6 is provided.

As shown in FIG. 12, the counterweights 22h1, 22h2 are stopped in a state of being almost in contact with each other while surrounding the bolt 13 in the initial state. In addition, the counterweights 22h1, 22h2 are slightly separated from the barrel rear end 11a.

As shown in FIG. 13, when the bullet is shot, the barrel 11 receives the recoil and retreats together with the bolt 13 located at the rear end. Thus, the barrel located at rear end 11a abuts on the counterweight 22h1 located near the barrel 11. As a result, the counterweights 22h1, 22h2, which are almost in contact with each other, receive the recoil. Thus, the kinetic energy moving rearward can be transferred. Accordingly, the counterweights 22h1, 22h2 begin to move rearward in a state of being almost in contact with each other.

FIG. 14 shows the stopped state. Before reaching the stopped state, two counterweights 22h1, 22h2 move rearward in a state of being almost in contact with each other and then the counterweight 22h1 stops first and the counterweight 22h2 stops after a minute time. As shown in FIG. 14, the two counterweights 22h1, 22h2 are stopped with a time difference and located at the positions separated from each other.

The counterweights 22h1, 22h2 receive the recoil while surrounding the bolt 13 and the counterweights 22h1, 22h2 stop after that. Namely, a plurality of counterweights is arranged surrounding the axial line of the trajectory. Consequently, the counterweights 22h1, 22h2 are located at the position surrounding the axial line of the trajectory when the barrel 11 transmits the recoil to the counterweights 22h1, 22h2 and when the counterweights 22h1, 22h2 are stopped. Thus, the barrel 11 is not displaced from the axial line of the trajectory and the trajectory of the bullet is not affected.

FIG. 15 to FIG. 17 show the initial state of the low recoil firearm by a schematic diagram concerning a modified example where the counterweights are arranged on the barrel 11. In the modified example shown in FIG. 15, counterweights 22i1, 22i2 are arranged on an upper side of the barrel 11 and counterweights 22j1, 22j2 are arranged on a lower side of the barrel 11. In addition, a barrel front end member 11b is formed on the barrel 11 at the portion located nearer to the end of the barrel 11 so that the barrel front end member 11b abuts on the counterweights 22i1, 22i2, 22j1, 22j2 when the barrel 11 is moved by receiving the recoil.

As described above, a plurality of counterweights 22i1, 22i2, 22j1, 22j2 is arranged sandwiching the axial line of the trajectory and facing with each other. Consequently, the counterweights 22i1, 22i2, 22j1, 22j2 are located at the position sandwiching the axial line of the trajectory when the barrel 11 transmits the recoil to the counterweights 22i1, 22i2, 22j1, 22j2 and the counterweights 22i1, 22i2, 22j1, 22j2 are stopped. Thus, at least the barrel 11 does not displace the axial line of the trajectory in the vertical direction and the trajectory of the bullet is not affected.

In the modified example shown in FIG. 16, only the counterweights 22i1, 22i2 are arranged on an upper side of the barrel 1. In the modified example shown in FIG. 17, only the counterweights 22j1, 22j2 are arranged on a lower side of the barrel 11. Since the low recoil firearm is not symmetrical in the vertical direction, the recoil can be reduced as a whole with good balance by arranging the counterweights 22i1, 22i2, 22j1, 22j2 on the upper side or the lower side of the barrel 11.

FIG. 18 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

In the previous examples, the number of the counterweights is two. However, the number of the counterweights is not limited to two. It is possible to use four counterweights 22k1, 22k2, 22k3, 22k4 as shown in the figure. When the four counterweights 22k1, 22k2, 22k3, 22k4 are used, the recoil transmitted from the barrel 11 can be distributed more finely by stopping the counterweights 22k1, 22k2, 22k3, 22k4 separately four times. Thus, the recoil felt by the user can be reduced.

FIG. 19 and FIG. 20 show the low recoil firearm concerning a modified example by a schematic diagram. FIG. 19 shows the initial state and FIG. 20 shows the stopped state.

This modified example is the low recoil firearm of semiautomatic type. The barrel 11 and the bolt 13 independently receive the recoil and the barrel 11 and the bolt 13 are slid rearward. Each of two pairs of counterweights 22m1, 22m2 and counterweights 22n1, 22n2 receives the recoil transmitted from the barrel 11 and the recoil transmitted from the bolt 13.

The counterweights 22m1, 22m2 are arranged on an upper side with respect to the trajectory of the barrel 11 as a reference. The counterweights 22m1, 22m2 are supported by the slide rail 21, which is supported by a not-illustrated frame or the like at the upper side, so that the counterweights 22m1, 22m2 can be slid in the front-rear direction. In addition, the counterweights 22m1, 22m2 are provided with the stop mechanism similar to the stop mechanism shown in FIG. 4 to FIG. 6. The counterweights 22m1, 22m2 receive the recoil when the barrel rear end 11a is retreated.

The counterweights 22n1, 22n2 are arranged on a lower side with respect to the trajectory of the barrel 11 as a reference. The counterweights 22n1, 22n2 are supported by the slide rail 21, which is supported by a not-illustrated frame or the like at the lower side, so that the counterweights 22n1, 22n2 can be slid in the front-rear direction. In addition, the counterweights 22n1, 22n2 are also provided with the stop mechanism similar to the stop mechanism shown in FIG. 4 to FIG. 6. The counterweights 22n1, 22n2 receive the recoil when the bolt 13 is retreated.

When the bullet is shot, the barrel 11 begins to move backward and the barrel 11 abuts on the counterweights 22m1, 22m2, the counterweights 22m1, 22m2 receive the recoil and begin to move backward. In addition, although the bolt 13 also moves backward when the bullet is shot, the bolt 13 abuts on the counterweights 22n1, 22n2 after the bolt 13 moves by a predetermined distance. Thus, the counterweights 22n1, 22n2 receive the recoil and begin to move backward.

Similar to the other examples, the counterweights 22m1, 22m2 and the counterweights 22n1, 22n2 are stopped with a time difference from each other. Although the user of the low recoil firearm receives the recoil when the counterweights are stopped, since the user receives the distributed recoil, the user feels that the recoil is low.

By adopting the above described configuration, fine adjustment can be performed by the counterweights 22m1, 22m2 and the counterweights 22n1, 22n2 depending on the barrel 11 and the bolt 13. Thus, the recoil transferred to the user can be reduced.

As described above, the low recoil firearm includes a plurality of members (the barrel 11 and the bolt 13) for causing a recoil, and a group of the plurality of counterweights (the counterweights 22m1, 22m2 and the counterweights 22n1, 22n2) is independently provided on each of the plurality of members for causing the recoil.

FIG. 21 is a schematic diagram of the initial state of the low recoil firearm concerning a modified example.

The weight of the counterweights 22p1, 22p2 is smaller than the weight of the counterweights shown above. It is not necessarily beneficial to increase the weight of the counterweights as heavy as possible. The weight of the counterweights should be adjusted depending on the low recoil firearm.

FIG. 22 and FIG. 23 show the low recoil firearm concerning a modified example by a schematic diagram. FIG. 22 shows the initial state and FIG. 23 shows the stopped state.

In the previous examples, the barrel rear end 11a moves rearward and directly abuts on the counterweights or the bolt 13 moves rearward and directly abuts on the counterweights. On the other hand, in this modified example, a buffer material 24 is arranged between the barrel rear end 11a and counterweights 22q1, 22q2. The buffer material 24 is formed of a hard resin or aluminum, for example. The material of the buffer material 24 is selected from the materials softer than the barrel rear end 11a and the counterweights 22q1, 22q2.

In the initial state shown in FIG. 22, a clearance is formed between the barrel rear end 11a and the buffer material 24, and a clearance is also formed between the buffer material 24 and the counterweights 22q1, 22q2. When the bullet is shot, the barrel 11 begins to move backward by the recoil, the barrel rear end 11a abuts on the buffer material 24 first and the barrel 11 further moves backward together with the buffer material 24. When the buffer material 24 abuts on the counterweight 22q1, the recoil received by the barrel 11 is instantaneously transmitted to the counterweights 22q1, 22q2.

At this time, even if the impact is applied to the barrel rear end 11a and the counterweights 22q1, 22q2, since the buffer material 24 is made of the material softer than the barrel rear end 11a and the counterweights 22q1, 22q2, the barrel rear end 11a and the counterweights 22q1, 22q2 are not damaged.

After that, the counterweights 22q1, 22q2 are sequentially stopped after a minute time by the stop mechanism. Thus, the recoil is distributed.

As described above, the low recoil firearm includes the barrel rear end 11a for causing the recoil and the buffer material 24 is placed between the counterweights 22q1, 22q2 and the barrel rear end 11a.

Note that it goes without saying that the present invention is not limited to the above-mentioned embodiments. Although it is to those skilled in the art, the following are disclosed as the one embodiment of this invention.

• • Mutually substitutable members, configurations, etc. disclosed in the embodiment can be used with their combination altered appropriately.
  • Although not disclosed in the embodiment, members, configurations, etc. that belong to the known technology and can be substituted with the members, the configurations, etc. disclosed in the embodiment can be appropriately substituted or are used by altering their combination.
  • Although not disclosed in the embodiment, members, configurations, etc. that those skilled in the art can consider as substitutions of the members, the configurations, etc. disclosed in the embodiment are substituted with the above mentioned appropriately or are used by altering its combination.

DESCRIPTION OF THE REFERENCE NUMERALS

1: low recoil firearm; 11: barrel; 11a: barrel rear end; 11b: barrel front end member; 12: part of frame; 12f: female screw hole; 13: bolt; 21: slide rail; 21a: planar portion; 21b: columnar portion; 22 (22a, 22a1, 22a2, 22b, 22b1, 22b2, 22g1, 22g2, 22h1, 22h2, 22i1, 22i2, 22j1, 22j2, 22k1, 22k2, 22k3, 22k4, 22m1, 22m2, 22n1, 22n2, 22p1, 22p2, 22q1, 22q2) . . . counterweights; 22c . . . groove; 22d . . . circular recessed portion; 22e . . . through hole; 22e1 . . . large diameter portion; 22e2 . . . small diameter portion; 22f . . . female screw hole; 23 . . . bolt; 23a . . . head portion; 23b . . . screw portion; 24 . . . buffer material

Claims

1. A low recoil firearm provided with a plurality of counterweights, wherein the number of the plurality of counterweights is two or more, anda stop mechanism for separately stopping each of the plurality of counterweights is provided.

2. The low recoil firearm according to claim 1, wherein weights of the plurality of counterweights are equal to each other.

3. The low recoil firearm according to claim 1, wherein weights of the plurality of counterweights are different from each other.

4. The low recoil firearm according to claim 1, wherein the plurality of counterweights is arranged to surround an axial line of a trajectory.

5. The low recoil firearm according to claim 1, wherein the plurality of counterweights is arranged to sandwich an axial line of a trajectory.

6. The low recoil firearm according to claim 1, wherein the low recoil firearm includes a member for causing a recoil, anda buffer material is arranged between the plurality of counterweights and the member for causing the recoil.

7. The low recoil firearm according to claim 1, wherein the low recoil firearm includes a plurality of members for causing a recoil, anda group of the plurality of counterweights is independently provided on each of the plurality of members for causing the recoil.

8. The low recoil firearm according to claim 1, wherein the plurality of counterweights is connected with each other so that the plurality of counterweights can be separated from each other by a predetermined distance in a moving direction.

9. The low recoil firearm according to claim 1, wherein the plurality of counterweights is configured to be stopped independently from each other.

10. The low recoil firearm according to claim 1, wherein the plurality of counterweights is configured to be stopped by making the counterweights collide with a stopper member.

11. The low recoil firearm according to claim 1, wherein the plurality of counterweights is configured to be stopped by making the counterweights slide on a stopper member.