Note: Descriptions are shown in the official language in which they were submitted.
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Gas removal arrangement and barrel and/or weapon with a gas removal
arrangement
The invention is relating a gas removal arrangement for a barrel and /or a
pipe of a self-loading, gas operated action weapon (e.g. a machine gun) with
a gas cylinder which is connected for the purpose of interchange with the
barrel bore. Such gas removal equipment is, for example, known from DE
196 15 181.
The expression "barrel" in the following refers to the barrel with its groves
and lands as well as to a smooth weapon pipe. Directions such as on the top,
bellow, in the front, behind, right and left are given from the view of the
shooter for a weapon that is held in the firing position.
In so-called gas operated action weapons, where the loading mechanism is
powered by the munitions' gas pressure, a gas piston is arranged in a gas
cylinder. To a large extend the gas cylinder is closed on one end so that a
pressure chamber is formed between the gas piston's frontal face and the gas
cylinder's frontal face which forms a communicating connection with the
interior parts of the barrel. During firing, the munitions' gas enters into
this
pressure chamber as soon as the projectile has passed the connection point
between gas chamber and the barrel bore. The entering gases build up in the
pressure chamber so that the pressure affects the frontal surface of the
working piston.
Via a worlcing piston the resulting force operates an actuator rod, which is
part of the loading mechanism of the weapon and which causes the cartridge
feeding and removal, the loclcing, and if needed, the cocking of the trigger
mechanism. In fully automatic weapons this mechanic is activated as long
as the trigger is held in the shooting position. The detonation energy, which
is released during shooting, is thus partially diverted for the powering of
the
weapon.
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Customarily, the cross sections of the flow, the design of the gas piston, and
the pressure chamber are adjusted to a weapon in a certain way so that the
desired firing speed can be adjusted and overstress of the mechanical
actuator can be omitted. For this purpose (besides the radial connection to
the barrel) the pressure chamber is furnished on its frontal side with an
axial
gas release opening in order to regulate the pressure. Thus, the gas which
enters from the barrel into the gas cylinder is partially released from the
gas
cylinder andlor the pressure chamber into the surroundings so that the
pressure in the pressure chamber is relatively low compared to the barrel.
Such an embodiment is likewise known from DE 196 15 181.
There are also mechanisms where the amount of gas, which exits from the
barrel, enters the pressure chamber axially on the frontal side (see, for
example, DE 648 391). The amount of gas entering can be adjusted via a
locking screw. The ventilation of the gas cylinder, however, is achieved
here by the piston leaving the cylinder entirely and thus it is made possible
for the gas to exist.
With changes on the weapon and/or on the munitions the gas pressure
conditions in the barrel bore and/or the gas cylinder are also changing. For
example, if a normally equipped weapon - with a flash compressor - is
alternatively furnished with a silencer, the gas pressure increases in the
barrel bore and thus in the gas cylinder and/or in the pressure chamber.
With that the speed of the working piston increases. This in turn leads to
increased speed of the loading and/or repetition process of an automatic
weapon. The same effect occurs if another type of munitions is used (larger
propelling charge, higher bullet mass).
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The loading process, which is accelerated in this way, also increases the
firing speed. This is accompanied by an increased use of munitions and the
mechanical stress on the parts of the weapon increases drastically. The
unnecessary increase in munitions use can lead to logistic problems for the
military use of such weapons. More munitions need to be brought along and
need to be made available where the weapon is used without at the same
time improving the performance of the weapon accordingly. The higher
demand on the weapon results in an increase in wear and shorter intervals
for maintenance and repair.
It is difficult and it cannot be put into practice under operating conditions
to
continuously adjust the flow and pressure conditions at the gas removal
arrangement in order to stabilize the firing speed.
The object of the presented invention is to provide an improved gas removal
arrangement which at least in part eliminates the above mentioned problems.
This object is addressed with the subject of claim 1. The invention is
characterized in that the effective flow cross section is adjustable to a
weapon configuration by means of a separate inlet piece.
In this context weapon configurations are a certain set-up of a weapon
and/or the use of a certain kind of munitions with that weapon. With the use
of an inlet piece in the connecting channel between the barrel bore and the
gas cylinder in a very simple way an appropriate flow cross section can be
achieved by means of an a appropriately designed inlet piece. Thus various
inlet pieces with an appropriate flow cross section, which will be determined
for certain weapon configuration, can be exchanged without the need for
additional adjustments to the weapon.
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In the further modification according to claim 2 such an inlet piece, which
can be inserted into the gas removal arrangement, is designed in an
adjustable and/or removable form. To design the inlet piece into the gas
removal arrangement is advantageous because here it is easy to implement
the appropriate design and adaption for the use of such an inlet piece for
structural and production reasons.
According to claim 3 such an inlet piece may feature a variety of different
through bore-holes that then define the desired flow cross section according
to the desired operating position of the inlet piece. Basically, in this
manner
it can be "switched" back and forth between several kinds of operation.
According to claim 4 the adjustment takes place by turning or moving the
inlet piece in the gas removal arrangement.
The design according to claim 5, which locks into place, makes repeated
adjustments of appropriate operating positions easier.
Claim 6 is in regard to a further modification where a specially designed
indentation features effective surfaces which work together with a locking
device so that the at least one of the characteristics of regulator stopper,
resting surface, and mounting lock is achieved. Regulator stopper means in
this context that the adjustment of the inlet piece is inhibited beyond a
certain range; resting surfaces define the corresponding operating position in
the gas removal arrangement; mounting lock means that unintentional
removal is prevented by an appropriate locking effect between the locking
unit and the indentation. The indentation itself can be produced with
appropriate production methods (e.g. by turning, milling, grinding, precision
casting, inject molding and so forth). According to claim 7 an indicator
element is designed on the insertion through which the operation setting of
the inlet piece can be seen andlor felt by touch.
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Such an in indicator function is particularly important for weapons since this
way the shooter can determine the adequate operational setting either "with
one glance" or "with one touch".
The further modification according to claim 8 facilitates the operation of the
inlet piece, whereby a inner hexagon profile can be operated with a regular
tool and/or a slot can be operated with an easily available item (e.g. a
coin).
The claims 9 and 10 are concerning a barrel component with a gas release
arrangement according to the invention and/or a weapon with such a barrel
component.
In the following the invention is closer described with the help of
illustrations:
Figure 1 shows a longitudinal cut through the muzzle area of a barrel
with the gas removal device according to the invention,
Figure 2 shows an enlarged view of the gas removal area from figure 1,
Figure 3 shows a side view (from the right) of the gas removal
arrangement according to the invention,
Figure 4 shows a side view (from the left) of the gas removal
arrangement according to the invention,
Figure 5 shows a cross cut through the gas removal arrangement
according to the invention in the area of the gas channel,
Figure 6 shows a longitudinal cut (sectional plane A-A in figure 5)
which shows the locking and the safety mechanism.
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Figure 7 shows a perspective view of an inlet piece for the gas removal
arrangement according to the invention.
Figure 1 shows the muzzle area of a weapon with the barrel 1, where a flash
compressor 2 is arranged at the frontal end. Behind the flash compressor a
gas removal 3 is affixed to the barrel which is connected to the locking
mechanism, which is not pictured, via rods, which are also not pictured.
When the munitions is fired the ignited propellant gas catapults the bullet
out to the bullet casing through the barrel bore 4, which runs concentrically
to the so-called bore axis 6, to the front of the barrel muzzle thought the
flash compressor 2 in the direction of the target. As soon as the bullet has
passed the area of the gas removal 3, part of the propellant gas enters into a
tap bore hole 8, witch runs diagonally to the barrel bore 4 radial in the
barrel
1, and it is directed into a pressure chamber 14, which is formed by the gas
cylinder 12, and that via an adjacent gas channel 10 which runs in the gas
removal 3.
This area is pictured enlarged in Figure 2. A gas piston 16 runs in the gas
cylinder 12 which with appropriate fit rests in gliding form against the
interior wall of the gas cylinder 12. The fit between the outer surface of the
gas piston 16 and the cylindrical interior wall of the gas cylinder 12 is
chosen in a way that the gas piston 16 is arranged in the gas cylinder 12 in
movable and largely leak proof form. The surfaces which are gliding
alongside each other are appropriately mechanically finished (turning,
milling, grinding, and precision-grinding), and in order to increase
durability
they might be surface treated (hardened, chrome-plated, coated or such).
The design could also include compression rings.
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The propellant gas, which has entered into the pressure chamber 14, builds
up a working pressure between the frontal surface of the gas piston 16 and
the frontal surface of the gas cylinder 12 and/or the pressure chamber 14.
This pressure moves the gas piston 16 and thus the rods to the back whereby
the gas rods carries over the pressure impulse to the weapon actuator which
activates the locking and loading mechanism (both are not pictured).
The gas removal 3 and the gas cylinder 12, which are here pictured in one
piece, are closely connected to the barrel 1 by means of a collar 18. The
collar 18 can be shrunk-on with the appropriate fitting on a corresponding
outer casing area of the barrel 1. The axial position on the barrel 1 is
hereby
defined by an offset 20, against which the collar 18 rest with its end face.
The collar 17, and thus also the gas removal 3, are additionally axial and in
circumferential direction affixed to the barrel 1 by means of pins 22. These
pins can, for example, be dowel pins or conical pins which pull the collar 18
downwards in the area of the gas channel 10 (diagonal to the bore axis) to
the outer surface of the barrel 1, so that the outer opening of the tap bore-
hole 8 merges closely with the opening of the gas channel 10. This seal
prevents the loss of gas between the barrel 1 and the collar 18.
In the pictured embodiment the gas piston 16 is furnished on its frontal end
with an auxiliary piston 16a which in the basic position of the gas cylinder
16 (pictured in figure 2) partially enters the ventilation bore- hole 24. Some
of the gas propellant exits thought the ventilation bore-hole 24 to the front
thought the discharge nozzle 26 when the gas piston 16 has moved a little
backwards (under the effect of the propellant gas) so that the auxiliary
piston
16a uncovers the ventilation bore-hole hole 24. With this the pressure in the
pressure chamber 14 is reduced and the effect of the gas on the gas piston 16
(and thus to the rods with are attached to the back) is reduced. Thus a
"softer" pressure flow on the gas piston is achieved. With it the forces on
the adjacent rods and on the loading and/or locking mechanism are reduced
as well.
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In the gas channel 10 itself an inlet piece is 30 designed which is inserted
into a through-bore-hole 32, which runs diagonally to the gas channel 10 and
to the bore axis 6 (see also figure 5). In the illustrated embodiment the
inset
piece 30 features two bore-holes 10a and l Ob which cross at an angle of
about 90 , penetrate each other, and which feature different diameters.
In the position, which is illustrated in figure 2, the bore-hole 10a connects
the end of the gas channel 10, which is facing the barrel with its end which
in turn is facing the gas cylinder. By turning the inlet piece 30 by 90 it
can
be adjusted in a way so that the bore 10b connects the two ends of the gas
channel 10. Depending on the chosen through bore-hole l0a and/or l Ob the
flow cross section between the tap bore-hole 8 and the gas cylinder 12
changes and thus also the amount of overflowing gas changes. Between
inlet piece 30 and through bore-hole 32 a tight fit is designed, so that the
bore hole 10a or lOb, which is not activated and which does not align with
the gas channel, is sealed.
The option to adjust the flow cross section between the tap bore-hole 8 and
the gas cylinder 12 and/or the pressure chamber 14 in a fixed predefined way
permits to adjust the weapon to various operation modes in order to achieve
in both modes the optimum firing speed.
For example, the use of a silencer (not picture) instead of the use of a flash
suppressor 2 increases the gas pressure in the barrel bore 4. This increased
pressure would lead with the unchanged gas channel cross section 10; 10a,
or l Ob to an increase in gas pressure built up in the pressure chamber 14
with in turn would lead to higher acceleration of the gas piston 16.
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This in turn would increase the firing speed and thus would lead to increased
stress or wear on the locking and reloading mechanism. In the worst case
scenario it can lead to malfunctioning of the ejection mechanism and that the
time for reloading a new cartridge from the magazine is too short so that it
could reliably be transferred from the locking arrangement to the cartridge
chamber.
In order to keep the pressure increase in the pressure chamber 14 at a
constant level even with an increase in gas pressure in the barrel bore 4 the
inlet piece can be adjusted in a way so that a bore-hole l0a or l Ob connects
the tap bore 8 with the pressure chamber 14 with a smaller cross section.
The corresponding bore-hole l0a or 10b reduces in this way the overflowing
gas so that the pressure increases slowly and so that the firing speed remains
constant.
In the illustrated embodiment for munitions of NATO caliber 7.62 a bore
diameter of the bore-hole 10a and/or 10b is designed at 1.7 mm for the use
with a flash suppressor and a bore diameter of 1.2 mm for the use with
silencer. For other common calibers, which are used with assault rifles, the
diameters can lie between 0.5 and 2 mm. For other weapons and other
calibers, however, the corresponding diameters need to be adjusted and can
also range differently.
A combined positioning and locking mechanism is designed for the locking
of the inlet piece 30 in the through bore-hole 32 in the gas removal 3. Its
function can be seen in the sectional view in figure 6 as well as in figure 3,
4,5and7.
Figure 7 shows an enlarged perspective view of the inlet piece 30. On one
end the inlet piece features an adjusting head 34 which has on the side a
protruding indicator and a control blade 36.
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An inner hexagon profile 38 and a slot for operation40 is located on the
frontal surface of the adjusting head 34 (figure 3). Both serve the purpose to
insert appropriate tools or devices (e.g. a coin) in order to turn the inlet
piece
in the through bore-hole 32 for positioning the desired connecting bore-hole
l0a or lOb.
In figure 7 the two openings of the bore-holes l0a and l Ob can be seen in the
cylindrical shank area 42. At the end of the shank area 42 an indentation 44
is designed into which the locking device 46 can interlock. (Figure 6)
For the interconnection with the locking device 46 the indentation 44 works
the following way: The frontal end 52 of the locking device 46 engages in a
springy manner with the indentation 44. The appropriate spring force is
pretensioned via a pressure spring 48, which is arranged together with a
locking device 46 in a conductor 49, over a locking pin 50.
The two radial sides 54 and 56 of the indentation 44 (see figure 7) with
which the end 52 engages are determining the axial position of the inlet
piece in the through bore 32 and prevent the unintentional removal. The two
radial sides 54 and 56 are connected to each other by corner arcs 58 and 60.
The indentation 44 and the bore-holes 1 0a and l Ob are arranged in a way to
each other so that the corner arcs 58 and 60 each form a stopper in
circumferential direction, which together with the end 52 determine the final
turning position of the inlet piece 30 by aligning the bore-holes 10a, l Ob,
respectively, with the gas channel 10.
Finally, the indentation features two more stopping surfaces 62 and 64
which interact with the frontal surface 66 on the end 52 of the locking device
46.
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With the turning of the inlet piece 30 the edge 63 which separates the two
stopping surfaces 62 and 64 moves across the frontal surface 66 and hereby
presses the locking device against he spring force backwards. If a certain
turning point is passed, the frontal surface 66 presses under the effect of
the
feather 48 against the edge 63 and turns the inlet piece 30 further into its
final position where the appropriate bore 10 a or lOb is aligned with the gas
channel 10.
For the removal of the inlet piece 30 the locking device 46 has an actuating
pin 68 which can be reached from the outside via a channe170 (figure 4).
Above the actuating pin 68 the locking device (46) can be moved out of the
grip of the indentation 44 so that the inlet piece 30 can be pushed out of the
though bore-hole 32. A shoulder 72 at the locking device 46 and a
corresponding step 73 in the conductor 49 prevent the locking device from
sliding into the through bore-hole 32 when the actuating pin is completely
released (when the inlet piece 30 is removed).
In the embodiment described above the inlet piece 30 is designed with two
through bore-holes l0a and l Ob. In other embodiments, however, several
crosswise arranged through bore-holes could be designed so that more then
two different through bore-hole settings can be possible. There are also
embodiments were a respective inlet piece 30 only features one bore-hole
and where the apportioning of gas can take place by a respective exchange
of such inlet pieces.
In yet another embodiment the through bore-holes can be arranged next to
each other, that is in different axial positions on the shank 42. These bore-
holes can then be aligned with the gas channel 10 by appropriate in or out
movements of the inlet piece 30.
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The inlet piece 30 is then designed as a slider. Such a mechanism is to be
furnished with a respective loclcing device.
Additional embodiments and variations of the presented invention are
resulting for the expert in the context of the following patent claims.
