Note: Descriptions are shown in the official language in which they were submitted.
2145066
This invention relates to a silencer as defined in the preamble of claim l, as
it is known from
FR-A-684 938 (VERGNE).
This known silencer consists of an attachment piece that can be attached to
the muzzle of a
weapon, of an end piece, and, in between, of a series of rings that are
successively placed in
a centered manner, and that form the outer wall of the silencer, and between
each of which a
dividing wall featuring a bring opening is set, thus forming successive
chambers.
The individual rings differ from each other in terms of their length so that
only one single,
specific ring is associated with each longitudinal segment of the silencer.
It is known from FR-8-323 574 (HUMBERT) that the structural members that
constitute the
individual chambers can be arranged within a common outer barrel.
The terms used here -- such as front and back, or front and rear -- relate to
the firing
direction, with the front pointing in the firing direction and the back
pointing away from the
firing direction.
A contemporary, customary silencer is known from DE 17 03 420 B 1 or the
corresponding
U.S. Pat. No. 3,385,164 (WALTHER). Its middle piece has a cylindrical jacket
tube to
whose back the attachment piece is attached, with the end piece being attached
to its front.
The attachment piece can be screwed in a gas-tight manner onto an outside
thread attached to
the muzzle of a rifle. In addition to other elements, the jacket tube contains
several
successive chamber parts supported on each other, each of which is provided
with a
longitudinal jacket resting against the inside
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2145060
wall of the jacket tube, and a crossbar. The crossbar extends by and large
transversely to
the longitudinal jacket, and thus transversely to the longitudinal axis of the
silencer. In its
middle, it has a firing opening, from where it tapers outward towards the
front. The
chamber parts are centered by means of the jacket tube.
Similar silencers are known from the following: DE-PS 241 846 (BILLERBECK), DE-
OS 15
53 874 (H&K) and 28 24 546 (FEHSE), GB Patent 30 240/1909 (SMALL ARMS
COMPANY) and U.S. Pat. No. 1,017,033 (KENNEY) and 1,111,202 (WESTFALL).
The number and possibly also the shape of the chamber parts must principally
be adapted to
the weapon and to the ammunition used in it. Another aspect to consider in
this context are
the requirements for the silencer. It can be assumed that each chamber part
reduces the
muzzle report by about 4 db -- to the extent that only a limited number of
chamber parts are
used.
Overall, a silencer should always be as short as possible. This is because it
increases the
total length of the firearm that has been painstakingly shortened by other
design means, and
it furthermore adds weight to the muzzle, thus impairing the weapon's balance.
Although different weapons may have the same caliber and muzzle shapes, it is
still
necessary to manufacture and stock many silencers with different lengths, in
order to meet all
requirements. This heavy expenditure is a disadvantage.
The invention's task is to improve the initially mentioned, known silencer in
such a way that
it can be adapted to the particular requirements with minor effort.
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_2145066
The invention solves this problem by means of the object of claim 1, which
means an object
in which the features of this class are combined with the other features,
i.e., each chamber
part is attached according to a modular principle directly to the adjoining
chamber part, and
the outer walls of the successive chamber parts form the outer wall of the
silencer.
The successive outer walls of the chamber parts thus form the silencer's outer
wall. The
jacket tube necessary for the known silencer is thus eliminated.
In known silencers, the jacket tube directly limits the expansion chamber. It
must therefore
have a strength and wall thickness that is able to withstand the developing
gas pressure. The
longitudinal jackets of the known chamber parts essentially function as
spacing bushings. In
that way, they increase the silencer's weight considerably, something that is
a disadvantage
for the reasons mentioned earlier. Because of the elimination of the jacket
tube, the object
according to the invention has none of these disadvantages. The silencer
according to the
invention differs from known silencers not only because of its reduced weight,
but also
because of its lower manufacturing costs.
In addition, the jacket tube no longer determines the silencer's structural
length, because it is
eliminated here. Instead, this silencer can in each case be assembled
optionally, as desired,
from a number of suitable chamber parts in such a way that it is optimized in
respect to a
particular application area, such as the length of the barrel, the type of
cartridge, and the
desired silencing effect. To achieve this, it is only necessary that a
sufficient number of
chamber parts of the particular design must be manufactured, which is possible
in a simple
and reasonably-priced fashion, for example, by die-casting, but in particular
on automatic
lathes. During assembly, a large number of different silencers then can be
assembled by
suitably combining the chamber parts using a modular principle.
3
21450~~
A muzzle attachment to be placed on barrels for unrifled projectiles is known
from DE-OS 1
553 895 or the corresponding FR Patent 1 597 401 (OY TAMPELLA). Such muzzle
attachments are used to achieve a considerable ballistic improvement in the
flight path of the
unrifled projectiles, for example, projectiles fired from a mortar. But they
are not silencers.
Such muzzle attachments usually do not have a jacket tube. The known muzzle
attachment
consists of a stack of roughly plate-edge-shaped ring disks. Spacers are
positioned between
the individual ring disks. The stack is held together overall by many tie
rods. The muzzle
gases can escape to the outside along the entire length of the muzzle
attachment, directly
between the ring disks.
A similar arrangement is also known from AT-39 274 (LOTH), relating to a
silencer. This
silencer also has chambers held together in a similar manner by tie rods, as
is the case in the
above-mentioned silencers, each of which employs a jacket tube.
In the silencer according to the invention, the individual chamber parts can
be connected to
each other, to the attachment piece, and/or to the end piece, for instance, by
resistance
welding. Parts with a non-circular cross-section also can be connected to each
other in this
way.
According to a preferred version of the invention, however, each chamber part
is provided
with a circumferential threading at its front end and with a circumferential
threading that
complements the former at its rear end, whereby, for instance and preferably
so, it has a
female thread at its front end, and a male thread at its rear end. The end
piece and the
attachment piece each are also equipped with a male or female thread matching
these threads.
The direct attachment of the chamber parts -- to each other as well as to end
piece and
attachment piece -- by means of threads enables a particularly simple assembly
of the
silencer; in addition to a gas-tight connection. The combination of male and
female threads
offers the advantage of preventing any incorrect assembly, i.e., installation
of a chamber part
in the wrong direction. This is particularly important in the case of chamber
parts whose
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214506
silencing effect depends on the direction in which the muzzle gases flow
through them
(claims 2 to 4).
It is principally possible, and in the case of an arrangement of a larger
number of chamber
parts also advantageous, to associate a cylindrical centering segment with
each thread in the
known fashion. This ensures an exactly centered, mutual association of the
silencer elements
according to the invention.
In the case of a smaller number of chamber parts, for instance, five chamber
parts, the
centering effect of a fine screw thread is however already completely
adequate; this is true
especially when the chamber parts, plus their circumferential threads, were
manufactured
with the narrow tolerances that can be easily achieved with an automatic lathe
(claim 5).
The thread connections of the individual elements permit an easy disassembly
of the silencer,
for instance, for cleaning. But this also entails hazards: improper or
insufficient screwing of
the fme screw threads may result in damage, as may the use of unsuitable tools
for the
silencer elements.
According to another preferred version of the invention, all thread
connections, but at least
those among the chamber parts themselves, are fixed after assembly in an
essentially
inseparable fashion, for example, by over-crimping or centering the
circumferential joints.
In this way the chamber parts and possibly also the other elements of the
silencer can be
made of a relatively soft, easily machined material, which essentially would
not withstand
repeated unscrewing and
21450fifi
screwing without damage to the threads. If needed, cleaning can be
accomplished by
flushing (claim 6).
The chamber parts preferably consist of an easily machined aluminum alloy, as
does the end
piece. The attachment piece, which is subject to frequent screwing onto the
barrel muzzle of
the firearm onto which the silencer is to be placed and which must then again
be unscrewed
from it, may consist of a material that can be subjected to greater stress.
According to another embodiment of the invention, the outer wall of each
chamber part
essentially consists of a longitudinal jacket, whose end segments hold the
mutually
complementary circumferential threads. Preferably, the longitudinal jackets
are constructed
as circular cylindrical jackets. Such a construction of the chamber parts
enables a
particularly simple assembly of the silencer. The successive outer walls of
the longitudinal
jackets together form the outer wall of the silencer (claim 7).
A crossbar positioned inside each of the chamber parts that tapers outward
towards the front
in the manner of a funnel promotes the silencing action in the known manner
(claim 8).
The crossbar can be positioned at that end of the chamber part or the
longitudinal jacket that
carries the male thread.
According to a preferred version of the invention, the crossbar, however, is
positioned in a
middle sector of the outer wall of the chamber part, i.e., of the longitudinal
jacket, which
means in an area not taken up by the threads. When assembling the silencer, a
clamping tool
may be used on this area; the crossbar then supports the tool's engagement.
6
2245~6~
This again permits a thin-walled construction of the outer chamber wall, i. e.
, of the
longitudinal jacket, without having to worry about problems during assembly.
The same
advantage is achieved when the chamber part is clamped in the chuck of an
automatic lathe
during its manufacture. The crossbar is preferably connected integrally to the
longitudinal
jacket (claim 9).
As is known, the firing opening in each crossbar should be as small as
possible so that, after
the projectile has passed through, the narrowest possible choke point is
formed for the
powder gases that follow. Although a direct brushing of the projectile against
the wall is
prevented by dimensioning the firing opening properly, erosion at this point
will be very
high. This is why the firing opening can become wider after protracted use of
the silencer,
thus reducing the silencing effect.
To remedy this problem, another version of the invention provides that the
firing opening is
lined with a bushing that may consist of a material more resistant than that
of the chamber
part, such as steel (claim 10).
The effectiveness of the silencer according to the invention is further
enhanced in that the
end piece and/or the attachment piece are provided with an additional pressure
relief
chamber, especially since they already have the corresponding length, if they
are provided
with a male or female thread. The pressure-relief chamber formed in the end
piece is
preferably constructed as a diaphragm body that suppresses the muzzle flash
(claims 11 and
12).
As noted earlier, chamber parts with different dimensions and shapes can be
assembled so as
to form a silencer according to the invention; preferably, however, the
chamber parts of the
silencer have the same structural design. That prevents any mix-up during
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_2145Q66
assembly and, at the same time, achieves a particularly simple manufacturing
process.
The invention will be explained in greater detail with the help of the
enclosed diagram. The
only figure here illustrates, virtually to scale, a longitudinal section
through a currently
preferred embodiment of a silencer according to the invention.
The silencer shown is intended for the model G3 rifle made by the applicant.
It has a total
length of 255 mm; its maximum outside diameter is 40 mm and it protrudes 152
mm beyond
the muzzle of the G3 rifle.
According to the figure, the silencer consists of three main parts, i.e., an
attachment piece 2,
a middle part 4, and an end piece 6.
Attachment piece 2 consists of a longish tube widened like a cup in front and
preferably
consisting of aluminum; from back to front, it comprises the following in
succession: a tube
segment 8, a narrowed cylindrical adapter segment 10, a threaded segment with
an internal
threading 12, a stop shoulder 4 that extends radially inward, a passage 16
whose diameter
exceeds the diameter of a projectile fired from the rifle (not shown) only by
a small amount,
a chamber 18 tapering comically outward towards the front, and an extensively
widened cup
segment 20 with a fine female thread 22.
After the muzzle flash suppressor has been unscrewed from the muzzle of a G3
rifle,
attachment piece 2 is screwed onto the barrel muzzle with its internal
threading 12. In the
process, adapter segment 10 is pushed tightly onto a complementary adapter
segment of the
barrel muzzle, and the front of the barrel muzzle rests against stop shoulder
14. Stop
shoulder 14, internal threading 12 and adapter segment 10, internal threading
12, and adapter
segment 10 thus center attachment piece 2 exactly on the barrel muzzle.
Middle part 4 is made up of several chamber parts 24, in this case four such
parts that are
screwed together. One of these chamber parts 24 will be described below.
8
2L4~~~6
Each chamber part 24 consists of a high temperature aluminum alloy and has an
overall
circular-cylindrical, tube-shaped longitudinal jacket 26 with an overall
smooth, circular-
cylindrical inside wall and outside wall 28. The front end of longitudinal
jacket 26 is bored
and is provided with a fme female thread 30 that in terms of length and other
dimensions is
identical to the female thread 22 in cup segment 20 of attachment piece 2.
The rear end of longitudinal jacket 26 has a fine male thread 32 that in terms
of length and
dimension complements the fine female threads 22 and 30.
A crossbar 34 fills up the clear width of longitudinal jacket 26. It has the
shape of a funnel
that is concentric to longitudinal jacket 26 and becomes wider towards the
front; its edge in
the area between the two fme thread ends 30 and 32 is connected integrally
with the inside
wall of longitudinal jacket 26.
The front-facing inside wall of the funnel-shaped crossbar 34 does not form
any continuous,
truncated cone-shaped surface; instead it consists of a radially internal rear
truncated-cone
surface and a radially external front truncated-cone surface separated from
the former. The
internal truncated-cone surface has a smaller apex angle and blends into the
external
truncated-cone surface. This design of chamber part 24 enhances the silencing
effect.
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214066
The narrow point of funnel 34, thus fashioned, lies roughly in a radial plane
with the rear
end of longitudinal jacket 26. A tightly fitting bushing 36 of steel plate is
pressed into it and
is bent to the rear and radially outward around the rear end of the narrow
point. Steel
bushing 36 is thus inseparably and firmly connected with the funnel's narrow
point and lines
it. In consideration of all of the occurring tolerances, the inside clearance
of steel bushing
36 is dimensioned so that the projectile can just pass through without
brushing against it.
In the figure, four such chamber parts 24 are screwed together. The space of
the back
chamber part 24 located in front of crossbar 34 and the space of the front
chamber part 24
located behind crossbar 34 together form an expansion chamber whose outer wall
is made up
of the successive outer walls 28 of the two adjoining longitudinal jackets 26.
The muzzle of chamber 18 of attachment piece 2, which becomes wider towards
the front, is
positioned and dimensioned so that a relatively narrow ring-shaped gap is
created towards the
rear outer circumferential edge of steel bushing 36 or of crossbar 34 of the
rear-most
chamber part 22. The ring-shaped gap leads into a first expansion chamber that
is limited by
the following parts: the rear of crossbar 34 and the rear part of longitudinal
jacket 26 of the
rear-most chamber part 24, as well as the bottom of the cup-like extension 20
of attachment
piece 2.
End piece 6 is an essentially bowl-shaped body with a short tube socket 38,
one of whose
ends is closed off by an outwardly arched end wall 40. An exit opening 42 is
located in the
center of the end wall 40. The inside edge of exit opening 42 is countersunk
to a large
degree.
21~506~fi
The outside of tube socket 38 carries a male thread 44 whose dimensions match
the male
threads 32 of chamber parts 24.
The inside of tube socket 38 has an internal threading 46, into which is
screwed a diaphragm
body 48 that acts as a muzzle flash or flame suppressor. For this purpose,
diaphragm body
48 has a threaded ring 50 whose rear end is closed off with a radial plate 52.
An exit bore-
hole extends through the center of radial plate 52. The circumferential edge
of said bore-
hole extends all the way to the inside surface of the adjoining longitudinal
jacket.
Diaphragm body 48 can be made of an easily machined aluminum alloy, but it can
preferably
be made of a more resistant material. The exit bore-hole can be lined with a
steel plate
bushing, similar to bushings 36.
Diaphragm body 48 and end wall 40 of end piece 6 define a last expansion
chamber 49 that
is located at the very front.
Two pocket bore-holes 54 are provided -- on both sides of the exit opening 42 -
- in the
forward-facing outside surface of end wall 40; a wrench for turning end piece
6 and thus for
tightening all threads 16, 30, 34, 44, and 46, can engage said pocket bore-
holes, whereby the
rear, tube-like end of attachment piece 2, for example, can be held firmly in
a spring chuck.
Threads 16, 30, 32, 44, and 46 are preferably filled with a heat-resistant
putty or adhesive,
prior to screwing, or they are mortised or otherwise secured after tightening,
so that the
ready-assembled silencer can no longer be taken apart.
11
