JPH06257991A - Supporting structure for gun barrel - Google Patents

Abstract

PURPOSE:To absorb thermal expansion, processing error of a gun barrel by interposing an elastic element between a supporting part of a support and an outer periphery of the barrel in a supporting structure for supporting an intermediate part of the barrel by the part of the cylindrical support integral with a sliding breech of a gun. CONSTITUTION:A sliding breech 2 of a machine gun is supported to a cradle 4 supported to a carriage through a height unit 8, and a base end of a gun barrel 1 is mounted at an end of the breech 2 through a stepped spring 10. A cylindrical support 9 concentric with the barrel 1 is fixed to an end face of the breech 2. In this case, an annular cutout 9b is formed at a supporting part 9a of a part opposed to a longitudinal intermediate part of the barrel 1 of the support 9, and an annular supporting unit 11 is provided at the cutout 9b. The unit 11 is formed in a structure in which a pair of taper rings are provided between an inner ring and an outer ring made of elastic materials such as rubber, elastomer, etc., to absorb thermal expansion, processing error of the barrel 1 by elastic deformations of the materials.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a barrel supporting structure.

[0002]

2. Description of the Related Art A gun barrel attached to the breech of a machine gun or the like has conventionally been constructed so as to be easily attached and detached. Generally, as shown in FIG.
The base end portion of is connected to the breech portion 2 with a step screw 10. Then, in order to reduce the deflection (hanging amount) of the barrel 1 due to its own weight and reduce the amount of deflection of the barrel 1 with respect to the breech part 2, a tubular support 50 is fixed to the front end of the breech part 2, and this support 50 The outer peripheral surface of the intermediate portion of the barrel 1 is supported by the inward flange-shaped support portion 50a at the tip of the.

[Problems to be Solved by the Invention]

However, in such a conventional supporting structure for a barrel, a stepping screw 10 portion between the breech portion 2 and the barrel 1 and a portion between the barrel 1 and the supporting portion 50a of the support 50 are illustrated. Considering the thermal expansion of the barrel 1 associated with the firing of the bullet 18 shown in FIG.
Since b is provided, there is a technical problem that the dispersion of the impact points when shooting the gun, that is, the so-called shot dispersion becomes large and the hit rate decreases.

The following factors are generally conceivable as factors affecting the spray dispersion. A. Variation in weight and center of gravity of bullet 18 a. Variation in amount and properties of propellant c. Initial velocity variation of bullet 18 d. Aiming error e. External factors such as wind power. Changes in the orientation of the muzzle 1a due to the swing of the gun rack or barrel 1. Addition of lateral velocity to bullet 18 due to deflection of barrel 1

Here, the above-mentioned power supply related to the barrel 1. G.
The reason for the phenomenon of the term is as follows. When the bullet 18 is fired, high-pressure gas is rapidly generated in the barrel 1, and the high-pressure gas strongly pushes the bullet 18 toward the muzzle 1a. At that time, the barrel 1 vibrates. Due to this vibration, in the state where the gaps 2c, 2d, and b are provided in the step screw 10 portion or the support portion 50a of the support 50, first, the barrel 1 is mainly moved by the gap 2c of the step screw 10 and the primary deflection angle α. Shakes and changes the direction of the muzzle 1a. Next, the vibrating barrel 1 crashes into the inner surface of the support portion 50a, temporarily stops, then bounces in the opposite direction and once returns, and then further swings at the secondary deflection angle α ', and the muzzle 1a
Changes in the direction of the bullets 18 and causes variations in the direction in which the bullets 18 project. The gap b is the gap between the inner surface of the support portion 50a and the barrel 1, the gap 2c is the gap in the central axis direction of the step screw 10, and the gap 2d is the barrel 1 near the step screw 10.
And the breech section 2.

Before and after the bounce, the muzzle 1a swings in the opposite direction, and the swing speed before the bounce is higher. The bullet 18 is normally fired from the muzzle 1a during the primary and secondary runouts. Therefore, when the bullet 18 exits the muzzle 1a, the bullet 18 receives a lateral velocity with respect to the normal traveling direction.

As shown in FIG. 9, when the muzzle 1a makes a primary runout at a speed of Vt when the muzzle 18 exits the muzzle 1a, the muzzle 18 moves toward the muzzle 1a at a speed Vo and Mouth 1
It jumps out at a velocity V in a direction combined with the velocity Vt of a and deviates from the direction of the muzzle 1a. This deviating angle is
tan ⁻¹ Vt / Vo = β. For example, the velocity Vt of the muzzle 1a is 1 m / s, and the velocity of the bullet 18 is Vo = 10.
In the case of 00 m / s, β = 1/1000, which is a value that cannot be ignored because the hit rate is reduced. In addition, when the muzzle 1a makes a secondary shake at a velocity of Vt ′ when the bullet 18 exits the muzzle 1a, the angle of deviation is β ′.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional technical problems, and has a structure in which a base end portion of a barrel 1 is provided at a tip end portion of a breech portion 2 of a gun. Combine,
Support part 9a of a cylindrical support 9 that is integral with the breech part 2
With the structure for supporting the middle portion of the barrel 1 in the direction of the central axis, an elastic body (12 or 15 or 13, between the supporting portion 9a of the support 9 and the outer peripheral surface of the barrel 1 is provided. 14) is a barrel supporting structure characterized by interposing 14). And an elastic body (12 or 15 or 1
3, 14) can be given an initial compression amount.

[0009]

Function: Inside the barrel, with the intermediate part in the central axis direction of the barrel connecting the base end part to the turret part supported by the elastic body provided on the support part of the tubular support integrated with the turret part. If a bullet is supplied and shot at, the barrel will tend to swing.
Since the middle part of the barrel in the direction of the central axis is supported by the elastic body, the shake due to the shooting is buffered and suppressed well.

The primary deflection of the barrel caused by the shooting is buffered by the elastic deformation of the elastic body, and the barrel is swung back in the opposite direction, resulting in a secondary deflection. During this time, energy is absorbed by the elastic body.

However, the primary and secondary deflection angles of the barrel during firing are significantly reduced, and the deviation angle of the muzzle orientation from the normal direction is significantly reduced. Further, the velocity of the muzzle in the direction perpendicular to the muzzle direction is also reduced, so that the angle at which the bullet deviates from the muzzle direction is significantly reduced. As a result, the dispersion of shots is reduced. In other words, there is a certain amount of clearance at the joint between the breech and the barrel considering the thermal expansion of the barrel due to the firing of the bullet, the processing accuracy, etc. The gap between the support and the support can be made substantially zero by the elastic body, and the spraying can be made small. Note that the thermal expansion of the barrel, the processing accuracy, and the like that accompany the firing of the bullet are also absorbed by the elastic deformation of the elastic body.

If the elastic body is given an initial compression amount, the elastic body can be brought into a proper state and can be tightly interposed between the barrel and the support portion of the support.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 7 show an embodiment in which a support structure for a barrel according to the present invention is applied to a machine gun. First, the essential parts of the machine gun will be described with reference to FIGS. A front end portion of the swing 4 is swingably supported on the gun rack 5 by a pair of ear shafts 6, and a height device 8 is interposed between the gun rack 5 and the front end portion of the rock rack 4. There is. The turret portion 2 is supported on the cradle 4 via slides 7 on both sides at the front and rear ends thereof,
At the tip of the breech section 2, the base end of the barrel 1 is a step screw 10
Are combined by. Further, a breech hole 3 is arranged in the turret portion 2 so that a bullet 18 can be supplied into the barrel 1 by the breech hole 3. It should be noted that the stepped screw 10 may be replaced by a normal fitting connection between the breech portion 2 and the base end portion of the barrel 1.

A tubular support 9 concentric with the barrel 1 is fixed to the tip surface of the breech section 2, and the tip section forms a support section 9a having an inward flange shape. Faces the middle portion of the barrel 1 in the direction of the central axis. An annular support device 11 is provided in an annular notch 9b formed in the inner peripheral portion of the front end of the support 9a of the support 9 to elastically support the barrel 1. As shown in detail in FIG. 3, the support device 11 includes an inner ring 12, a pair of taper rings 13 and 14,
It has an outer ring 15 and a plurality of bolts 16, and has an inner ring 12, an outer ring 15 and a pair of taper rings 13, 14.
Is formed of an elastic body made of rubber or elastomer.

As shown in FIG. 4, the inner ring 12 has a slit 12a and is formed in an annular shape so that it can be elastically expanded or reduced in diameter, and its outer peripheral surfaces are located on both sides in the central axis direction. Cylindrical surface 12 in which tapered surfaces 12b and 12c that gradually decrease in diameter are formed symmetrically, and the inner peripheral surface is in close contact with the outer peripheral surface of barrel 1.
forming d. As shown in FIG. 4, the outer ring 15 has a slit 15a and has an annular shape, and can be elastically expanded or reduced in diameter, and the inner peripheral surface gradually expands to both sides in the central axis direction. The diametrically tapered surfaces 15b and 15c are formed symmetrically, and the outer peripheral surface forms a cylindrical surface 15d that is in close contact with the annular notch 9b.

As shown in FIGS. 3 and 5, one taper ring 13 has an annular shape with a trapezoidal cross section, and an inner peripheral surface forms a tapered surface 13a and an outer peripheral surface forms a tapered surface 13b. There is. As shown in FIGS. 3 and 6, the other taper ring 14 has an annular shape with a trapezoidal cross section, and an inner peripheral surface forms a tapered surface 14a and an outer peripheral surface forms a tapered surface 14b.

The taper surface 13a on the inner peripheral surface of one taper ring 13 engages with one taper surface 12b of the inner ring 12, and the taper surface 13b on the outer peripheral surface of the one taper surface 13b with one taper surface 15b of the outer ring 15. Engage. Further, the taper surface 14a on the inner peripheral surface of the other taper ring 14 engages with the other taper surface 12c of the inner ring 12, and the taper surface 14b on the outer peripheral surface.
Engages with the other tapered surface 15c of the outer ring 15.
A plurality of (four in the embodiment) through holes 13c are formed in one taper ring 13 at predetermined circumferential intervals, and a plurality of through holes 13c are formed in the other taper ring 14 at predetermined circumferential intervals. Individual screw holes 14c are formed so as to correspond to the respective through holes 13c.

The support device 11 is an annular notch 9b formed in the inner peripheral portion of the front end of the support portion 9a of the support 9 in a state where both taper rings 13 and 14 are combined between the outer ring 15 and the inner ring 12. And the outer peripheral surface of the barrel 1. In this state, the cylindrical surface 1 which is the outer peripheral surface of the outer ring 15
5d faces the cylindrical surface of the annular notch 9b, and the inner ring 1
The cylindrical surface 12d, which is the inner peripheral surface of the barrel 2, faces the outer peripheral surface of the barrel 1. In the assembling work of the support device 11, the slit 12a in the inner ring 12 elastically expands and the outer ring 1
5, the slit 15a is elastically contracted, so that the slit 15a can be easily formed.

From this state, the bolts 16 are inserted through the through holes 13c of the one taper ring 13 and screwed into the screw holes 14c of the other taper ring 14, whereby the two taper rings 13, 14 are tightened. This allows
Outer taper surfaces 13b, 1 of both taper rings 13, 14
The outer ring 15 in which the 4b and the tapered surfaces 15b and 15c are engaged with each other.
Elastically expands in diameter and compressively deforms, and the inner ring 12 in which the tapered surfaces 13a, 14a and the tapered surfaces 12b, 12c of the inner circumferences of the tapered rings 13, 14 engage with each other elastically contracts in diameter. Compressed and deformed, both taper rings 1
Coupled with the elastic compression deformation of 3, 14, the barrel 1 is tightly supported by the support portion 9a of the support 9 without a gap.

Thus, the inner ring 12 and the outer ring 15 which are elastic bodies are given a predetermined initial compression amount according to the screwing amount of the bolt 16. At that time, the slit 12a is reduced in the inner ring 12 and the slit 15a is reduced in the outer ring 15.
a expands. The processing error is due to the gap c between the breech 2 and the barrel 1 at the same position as the conventional example of the step screw 10 portion,
d is absorbed, or the inner ring 12 or the outer ring 15 or both tapered rings 13 and 14 which are elastic bodies are elastically deformed and absorbed.

In this way, the base end of the barrel 1 is connected to the breech 2
Support device 1 in which the intermediate portion of the barrel 1 in the direction of the central axis is provided on the support portion 9a of the support 9
When the bullet 18 (not shown) is supplied into the barrel 1 by the breech bolt 3 while being elastically supported by the barrel 1, the barrel 1
Tends to swing. Since the middle portion of the barrel 1 in the direction of the central axis is tightly supported by the support device 11 without a gap, the shake due to the shooting is suppressed well.

Specifically, the primary runout of the barrel 1 caused by the shooting is damped by elastic deformation of the inner ring 12, the outer ring 15, and the pair of taper rings 13 and 14, which are elastic bodies, After that, the barrel 1 is swung back in the opposite direction to cause secondary shake. In the meantime, the tapered surfaces 12b, 12c, 15b, 15c of the inner ring 12 and the outer ring 15
And the tapered surfaces 13a, 13 of the taper rings 13, 14
b, 14a, 14b and inner ring 12, outer ring 15, which is an elastic body, and a pair of taper rings 13, 14
Energy is absorbed by the internal loss of the barrel, and the swinging of the barrel 1 is suppressed. The elastic forces of the inner ring 12, the outer ring 15, and the tapered rings 13 and 14 can be adjusted by changing the screwing amount of the bolt 16 and changing the initial compression amounts thereof.

However, the deviation amount of the direction of the muzzle 1a from the normal direction at the time of shooting is remarkably reduced by the decrease of the primary and secondary deflection angles (α, α'shown in FIG. 8) of the barrel 1. , The velocity of the muzzle 1a in the direction perpendicular to the direction of the muzzle 1a (see FIG.
The difference between Vt and Vt ′) and the absolute value thereof also becomes small. As a result, the dispersion of shots is reduced. That is, FIG.
As shown in FIG. 3, while maintaining the gaps c and d in the stepped screw 10 to be slightly smaller than the conventional one, the support device 11 is used to form the gap (conventional gap b) between the barrel 1 and the support portion 9a of the support 9. Therefore, it is possible to reduce the spray dispersion to substantially zero. The gap between the barrel 1 and the support portion 9a of the support 9 is set to substantially 0 by the support device 11, and the orientation of the barrel 1 is stabilized. Bullet 1 with slightly smaller size than before
It is possible to satisfactorily absorb the thermal expansion of the barrel 1, the processing accuracy, etc. associated with the firing of 8.

By the way, in the above embodiment, the inner ring 12, the outer ring 15 and the pair of taper rings 13, 1 are provided.
Although both 4 are formed of an elastic body, if at least one of the inner ring 12 or the outer ring 15 or the pair of taper rings 13 and 14 is formed of an elastic body, the barrel 1 and the support 9 are supported. It is possible to make the gap between the portion 9a and the portion 9a substantially zero and to elastically support the barrel 1.

[0025]

As can be understood from the above description,
According to the barrel supporting structure of the present invention, since the middle portion of the barrel is supported via the elastic body, thermal expansion of the barrel, processing error and the like can be absorbed by elastic deformation of the elastic body.
In addition, the amount of deflection of the barrel when firing a bullet can be reduced, the deviation angle of the muzzle direction from the normal direction can be reduced, and the speed of the deflection of the barrel can be reduced, and it deviates from the muzzle of the bullet. The angle can be reduced. As a result, it has become possible to reduce the shot-scattering by using a simple structure in which an elastic body is added, and to significantly increase the hit rate.

[Brief description of drawings]

FIG. 1 is a cross-sectional front view of a barrel supporting structure according to an embodiment of the present invention.

FIG. 2 is a rear view showing the same with a partial incision.

FIG. 3 is a sectional view showing a main part of the same.

FIG. 4 is a perspective view showing the inner ring and the outer ring in an exploded manner.

FIG. 5 is a diagram showing a main part of one taper ring of the same.

FIG. 6 is a diagram showing a main part of the other taper ring.

FIG. 7 is a sectional view showing a stepped screw portion of the same.

FIG. 8 is a sectional view showing a conventional example.

FIG. 9 is an explanatory view of the same operation.

[Explanation of symbols]

1: barrel, 2: breech, 3: breech, 4: swing, 5: gun shaft, 6: ear shaft, 7: slide, 9: support, 9a: support, 9b: annular notch, 10: Step screw, 11: support device, 12: inner ring (elastic body), 12a: slit, 12b, 12c: tapered surface, 12d: cylindrical surface, 1
3, 14: taper ring, 13a, 13b, 14a, 1
4b: tapered surface, 13c: through hole, 14c: screw hole, 1
5: outer ring (elastic body), 15a: slit, 15b,
15c: tapered surface, 15d: cylindrical surface, 16: bolt, 1
8: bullet.

Claims (2)

[Claims] 1. A base end portion of a barrel is coupled to a tip portion of a breech portion of a gun, and a support portion of a cylindrical support which is integral with the breech portion supports an intermediate portion in the central axis direction of the barrel. A support structure for a barrel, wherein an elastic body is interposed between a support portion of the support and an outer peripheral surface of the barrel. 2. A support structure for a barrel according to claim 1, wherein an initial compression amount is given to the elastic body.