[0001] The invention relates to the sector of sport guns.
[0002] More in detail, the invention relates to a compressed gas gun with firing impulse
compensation device.
[0003] In this type of gun, the push to launch the projectile is obtained by compressing
a gas, which can be air or a different gas, such as carbon dioxide.
[0004] Compression of the gas can take place at the time of firing, or prior to firing,
and in this case pulling the trigger causes its sudden expansion, with consequent
firing of the projectile.
[0005] The invention is described, purely by way of example, with reference to guns which
use special cylinders into which the shooter has already inserted a gas (generally
air) with pressure and, each time the trigger is pulled, a valve releases a small
quantity of gas sufficient for firing.
[0006] The firing impulse, commonly known as recoil, is the movement made by a weapon at
the moment in which a projectile is hurled or exploded, and usually creates unwanted
effects for the shooter, also jeopardising the precision of the shot.
[0007] In particular, recoil occurs at the moment in which the action of the force which
pushes the projectile starts. In the case of a gun provided with a barrel, as the
compressed gas which is released when the trigger is pressed can only expand horizontally,
it pushes the projectile forwards and the breech, and consequently the weapon, backwards.
[0008] The use of different firing impulse compensation systems, and which limit the effect
of recoil, on compressed gas guns, is known.
[0009] For example, the patent
DE 102009011718 A1 discloses a firing impulse compensation system comprising a compensation mass which
acts pushed in a direction opposite to that of the fired projectile, balancing the
forces acting on the weapon.
[0010] In particular, said compensation mass is kept in an initial position by retaining
means comprising a magnet and the magnetic contact produced is then broken by the
pushing action of a portion of compressed gas released when the trigger is pressed,
which acts, at least indirectly, on said mass.
[0011] Said portion of compressed gas flows into a connection duct which places the barrel
of the gun in communication with the compensation mass.
[0012] Once the retaining magnetic contact has been broken, and therefore the compensation
mass has been released, this is launched in a direction opposite to the projectile
by means of a preloaded coil spring, interposed between said compensation mass and
said connection duct.
[0013] A firing impulse compensation device of this type has an evident drawback: the push
of the compensation mass is entrusted to additional mechanical elements which are
difficult to calibrate, such as the coil spring, also causing an increase in the weight
of the gun, an addition of components which can also be subject to wear and interact
with difficulty with one another, also causing friction.
[0014] Even more disadvantageously, the elasticity of said spring can vary over time, jeopardising
the efficacy of the device.
[0015] If the spring were to be replaced, it would be necessary to disassemble and open
the whole gun with lengthy and laborious operations, also with the risk of varying
the entire constructive balance thereof.
[0016] Moreover, the efficacy of the absorbing effect of the firing impulse has the disadvantage
of depending also on parameters correlated to the projectile used, such as weight,
calibre, shape, and on characteristics of the weapon, such as dominating compression,
barrel wear, as well as opening time of the discharge valve of the compressed gas.
Optimal setting of the gun, and therefore also of the firing impulse compensation
device, is therefore extremely difficult and necessarily subject to be varied in time,
making it necessary to disassemble and reassemble the weapon, without it being possible
to check the new calibration until the weapon is once again completely reassembled.
[0017] The invention intends to overcome these limits, by producing a compressed gas gun
provided with firing impulse compensation device which can be easily adjusted and
calibrated in time, is effective, light, precise, which is not subject to wear and
which does not cause losses of load of the compressed gas.
[0018] These aims are achieved with a compressed gas gun with firing impulse compensation
device comprising:
- a compressed gas reservoir;
- a barrel in which a projectile runs;
- a firing mechanism for said projectile which can be activated by means of a trigger
for controlling metered delivery of said compressed gas,
wherein said firing impulse compensation device comprises a compensation mass which
is kept in the initial position by retaining means and which, during the movement
of said projectile through said barrel, is pushed in a direction opposite to the projectile
and is released by said retaining means at least indirectly by means of the compressed
gas acting on the projectile and passing into a connection duct interposed between
said barrel and said mass,
characterized in that the quantity of compressed gas suitable for releasing said mass can be calibrated
by means of adjustment means accessible from the outside of said gun.
[0019] According to a first embodiment of the invention, said adjustment means are arranged
along said connection duct to modify the section thereof.
[0020] In particular, said adjustment means comprise a screw provided with a threaded portion
and a smooth end needle, where the reversible tightening of said screw causes a greater
or lesser penetration of said needle into said duct.
[0021] According to a further embodiment of the invention, said retaining means comprise
a toroidal gasket made of elastic material and a perforated flange provided with a
rim for housing said gasket suitable for retaining said compensation mass in the initial
position by interference.
[0022] In particular, said compensation mass, at its end facing towards said barrel, comprises
a groove suitable for cooperating with said gasket by interference.
[0023] According to a particularly advantageous embodiment of the invention, said perforated
flange has a section at least partly of frustoconical shape, with a flaring increasing
towards said compensation mass.
[0024] According to a further embodiment of the invention, said compensation mass, released
from the retaining means, is pushed inertially, due to the effect of the impulse of
the compressed gas only, into a tubular guide.
[0025] A compressed gas gun provided with firing impulse compensation device according to
the invention has many advantages.
[0026] Firstly, the push of the compensation mass is entrusted entirely to the pressing
force of the compressed gas which not only releases this mass from said retaining
means, but can be suitably metered also to ensure that the mass moves away in a direction
opposite to the projectile.
[0027] The quantity of compressed gas suitable for releasing and moving said mass can, in
fact, be calibrated by means of specific adjustment means that are advantageously
accessible from the outside of the gun and which therefore make it possible for the
gun to be constantly adjusted, without the need to disassemble and reassemble it.
[0028] The user of the gun, by acting on said adjustment means, can modify the quantity
of compressed gas acting on the compensation mass, to take account of a variety of
disturbing environmental factors or wear factors which may occur and which can interfere
with the firing precision and with the efficacy of the firing impulse compensation
device.
[0029] The arrangement of said adjustment means along the connection duct between the barrel
and the compensation mass makes adjustment directly effective on the retaining means.
[0030] Adjustment advantageously takes place promptly and precisely, also due to the type
of screw selected: by modifying the section of the connection duct with the smooth
end needle, this ensures a micrometric modification of the area of said duct, due
to the pitch of the thread of the screw.
[0031] To facilitate release of the compensation mass from the retaining means and optimise
the action of the compressed gas acting on this mass, the flange is provided with
a frustoconical shaped flaring. This design choice increases the pushing surface on
which the gas acts, thus making increasingly small quantities of gas necessary for
the release and movement of said mass, being said quantities of gas well directed.
[0032] The advantages of the invention will be more apparent below, in the description of
a preferred embodiment, provided by way of non-limiting example, and with the aid
of the drawings, wherein:
Fig. 1 represents, in a longitudinal section, a compressed gas gun provided with firing
impulse compensation device according to the invention;
Figs. 2 and 3 represent, in a longitudinal section, a detail of the gun of Fig. 1
in two operating steps of the firing impulse compensation device;
Figs. 4 and 5 represent, in a longitudinal section, a detail of the firing impulse
compensation device according to the invention in two possible adjustment steps.
[0033] With reference to Fig. 1, there is shown a compressed gas gun 1 with firing impulse
compensation device 2 according to the invention.
[0034] Said gun 1 substantially comprises:
- a compressed gas reservoir 3;
- a barrel 4 provided with a longitudinal axis x in which a projectile runs;
- a firing mechanism for said projectile which can be activated by means of a trigger
5 for controlling metered delivery of said compressed gas.
[0035] A firing impulse compensation device 2 is mounted on said gun 1.
[0036] With particular reference to Figs. 2 and 3, said device 2 comprises a compensation
mass 6, cylindrical in shape, which slides inside a specific tubular guide 11, arranged
on the weapon 1 on the opposite side with respect to said barrel 4 and aligned along
its longitudinal axis x.
[0037] In the initial condition represented in Fig. 2, i.e. before firing, said mass 6 is
kept in the initial position, namely in physical contact with the portion of said
guide 11 closest to the barrel 4 of the gun, by means of retaining means.
[0038] Said retaining means, as illustrated, comprise a toroidal gasket 9 made of elastic
material, of known O-Ring type, and a perforated flange 10.
[0039] In particular, said flange 10 is provided with a rim 12 for housing said gasket 9.
[0040] Said gasket 9 is suitable for retaining, by interference, said compensation mass
6 which is provided, in its end facing towards said barrel 4, with a groove 13 to
contain said gasket 9.
[0041] In the final condition represented instead in Fig. 3, i.e. after firing of the shot,
said mass 6 has varied its position, released from said retaining means and launched
inside said guide 11 in a direction opposite to that of the projectile, and thus moved
away from the barrel 4.
[0042] Both the release of the mass 6 from the gasket 9, and its thrust and its inertial
motion are caused due to the impulse of the compressed gas.
[0043] In fact, a connection duct 7 is arranged between said barrel 4 and said guide 11,
aligned along said longitudinal axis x, having a capillary section if placed in relation
to the diameters of said barrel 4 and of said guide 11.
[0044] Said connection duct 7 is suitable for enabling the passage of a metered quantity
of compressed gas, coming from said reservoir 3 and released by means of said firing
mechanisms, towards said compensation mass 6.
[0045] Said flange 10, interposed between said guide 11 and said connection duct 7, is suitably
perforated to also enable the passage of said gas.
[0046] In a possible embodiment, not shown, the hole of said flange has a section at least
partially of frustoconical shape, with a flaring with increasing section facing towards
said compensation mass.
[0047] With particular reference to Figs. 4 and 5, adjustment means are arranged along said
connection duct 7, orthogonally to its axis x, said adjustment means being suitable
for modifying the dimension of the section of said connection duct.
[0048] Said adjustment means comprise a screw 8 suitable for cooperating with a micrometric
thread obtained in a seat 7'.
[0049] In particular, said screw 8 is provided with a threaded portion 8' cylindrical in
shape and headless, and with a smooth end needle 8", suitable for sliding in a specific
seat 7" obtained in said duct 7.
[0050] Tightening or loosening of said screw 8, which can be obtained by means of a hexagonal
key acting directly from the outside of the gun, respectively causes a greater (Fig.
4) or lesser (Fig. 5) penetration of said needle 8" into said duct 7 and therefore
a narrowing or widening of its free section.
[0051] Operation of the firing impulse compensation device 2 according to the invention
is described below.
[0052] To calibrate the firing impulse compensation device, the user, in relation to his/her
experience, to the features of the gun, to the type of projectile used, to external
environmental factors, etc., acts on the adjustment means, tightening or loosening
the corresponding screw 8 to decrease or increase the section of the connection duct
7 for passage of the compressed gas.
[0053] When the user presses the trigger 5, a part of the compressed gas provided in the
reservoir 3 is expelled and directed inside the barrel 4 of the gun and, expanding,
strikes the projectile exerting the firing force thereon.
[0054] In the passage from the reservoir 3 to the barrel 4 of the gun, a quantity of compressed
gas, suitably metered and calibrated by means of said adjustment means, passes through
said connection duct 7 reaching the compensation mass 6.
[0055] The force of the compressed gas releases the mass 6 from the O-Ring retaining gasket.
[0056] Subsequently, the compensation mass 6 is pushed inertially, due to the effect of
the impulse of the compressed gas only, and moves in the guide 11 from the initial
position represented by Fig. 2 to the final position represented by Fig. 3.
[0057] The air present in the guide 11 and shifted from the compensation mass 6 is discharged
from the gun 1 directly from the bottom opening of said guide.
[0058] Before firing again, the user restores the interference between the compensation
mass 6 and the retaining means by acting on the loading lever, to simultaneously move
the guide 11, the flange 10 and the gasket 9 back towards the end portion of the gun
in which the compensation mass 6 is located, so that it is once again coupled and
at the same time frees the entrance of the barrel 4 for positioning of a new projectile.
[0059] Once the interference has been restored between the flange 10 and the gasket 9 with
the compensation mass 6, acting in the opposite direction on the same lever, the compensation
mass 6 is moved back towards the barrel 4, i.e. to its initial position prior to firing.
[0060] Finally, if necessary, the user also acts on the screw adjustment means 8 to vary
and optimise compensation of the firing impulse for the next shot.
1. Compressed gas gun (1) with firing impulse compensation device (2) comprising:
- a compressed gas reservoir (3);
- a barrel (4) in which a projectile runs;
- a firing mechanism for said projectile which can be activated by means of a trigger
(5) for controlling metered delivery of said compressed gas, wherein said firing impulse
compensation device (2) comprises a compensation mass (6) which is kept in the initial
position by retaining means and which, during the movement of said projectile through
said barrel (4), is pushed in a direction opposite to the projectile and is released
by said retaining means at least indirectly by means of the compressed gas acting
on the projectile and passing into a connection duct (7) interposed between said barrel
(4) and said mass (6), characterized in that the quantity of compressed gas suitable for releasing said mass can be calibrated
by means of adjustment means accessible from the outside of said gun.
2. Compressed gas gun (1) with firing impulse compensation device (2) according to claim
1, characterized in that said adjustment means are arranged along said connection duct (7) to modify the section
thereof.
3. Compressed gas gun (1) with firing impulse compensation device (2) according to claim
1, characterized in that said adjustment means comprise a screw (8), provided with a threaded portion (8')
and a smooth end needle (8"), where the reversible tightening of said screw (8) causes
a greater or lesser penetration of said needle (8") into said duct (7).
4. Compressed gas gun (1) with firing impulse compensation device (2) according to claim
1, characterized in that said retaining means comprise a toroidal gasket (9) made of elastic material and
a perforated flange (10) provided with a rim (12) for housing said gasket suitable
for retaining said compensation mass (6) in the initial position by interference.
5. Compressed gas gun (1) with firing impulse compensation device (2) according to claim
5, characterized in that said compensation mass (6), at its end facing towards said barrel (4), comprises
a groove (13) suitable for cooperating with said gasket (9) by interference.
6. Compressed gas gun (1) with firing impulse compensation device (2) according to claim
4, characterized in that said perforated flange (10) has a section at least partially of frustoconical shape,
with flaring increasing towards said compensation mass (6).
7. Compressed gas gun (1) with firing impulse compensation device (2) according to claim
1, characterized in that said compensation mass (6), released from the retaining means, is pushed inertially,
due to the effect of the impulse of the compressed gas only, into a tubular guide
(11).