U.S. patent application number 12/225596 was filed with the patent office on 2009-05-21 for hydropneumatic braking and return system for barrel-recoil guns.
Invention is credited to Norbert Kohnen.
Application Number | 20090126558 12/225596 |
Document ID | / |
Family ID | 38115534 |
Filed Date | 2009-05-21 |
United States Patent
Application |
20090126558 |
Kind Code |
A1 |
Kohnen; Norbert |
May 21, 2009 |
Hydropneumatic Braking and Return System for Barrel-Recoil Guns
Abstract
The invention relates to a hydropneumatic braking and return
system for barrel-recoil guns having at least one working cylinder
(1) which can be arranged between the gun barrel (6) of the gun and
that mass (7) of the gun which does not recoil, contains a brake
fluid (4) and has displaceable working pistons (3) which are
arranged on a piston rod (2). In order to obtain a braking and
return system of simple construction for barrel-recoil guns, with
which it is simply possible, moreover, to take changes in different
shooting parameters into consideration, the invention proposes to
replace the braking cylinder of known systems with a simple working
cylinder (1) having a working piston (3), wherein the working
cylinder (1) is connected to a hydraulic accumulator (9) via a
separate controllable pressure relief valve (10), wherein the
pressure relief valve (10) can preferably be actuated in such a way
that a substantially constant brake-force profile results during
the recoil of the corresponding gun barrel (6).
Inventors: |
Kohnen; Norbert; (Viersen,
DE) |
Correspondence
Address: |
Klaus P Stoffel;Wolf & Samson
One Boland Drive
West Orange
NJ
07052
US
|
Family ID: |
38115534 |
Appl. No.: |
12/225596 |
Filed: |
March 9, 2007 |
PCT Filed: |
March 9, 2007 |
PCT NO: |
PCT/EP2007/002065 |
371 Date: |
October 29, 2008 |
Current U.S.
Class: |
89/43.01 |
Current CPC
Class: |
F41A 25/20 20130101 |
Class at
Publication: |
89/43.01 |
International
Class: |
F41A 25/20 20060101
F41A025/20 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 24, 2006 |
DE |
10 2006 014 155.5 |
Claims
1-6. (canceled)
7. A hydropneumatic braking and return system for a barrel-recoil
gun, comprising: at least one working cylinder arrangeable between
a gun barrel of the gun and a mass of the gun that does not recoil,
the cylinder including a displaceable working piston arranged on a
piston rod, and containing brake fluid; a hydraulic accumulator;
and a hydraulic control circuit including an adjustable pressure
limiting valve, the working cylinder connected to the hydraulic
accumulator via the adjustable pressure limiting valve of the
hydraulic control circuit, the hydraulic accumulator including a
hydraulic cylinder in which a separating piston separates a first
chamber, which is connected to the hydraulic control circuit, from
a second chamber, which is filled with a prestressed gas, so that
during a recoil movement of the gun barrel from a rest position to
a recoil end position, the displacement of the working piston
presses brake fluid from the working cylinder into the first
chamber of the hydraulic cylinder via the adjustable pressure
limiting valve and the gas in the second chamber of the hydraulic
accumulator is compressed as a result of displacement of the
separating piston, the brake fluid being pressed back into the
working cylinder upon relaxation of the compressed gas thereby
causing the gun barrel to advance to its rest position.
8. The hydropneumatic braking and return system according to claim
7, wherein the hydraulic control circuit contains at least one
throttle valve with which the speed of a flow of brake fluid which
is pressed back from the first chamber of the hydraulic accumulator
into the working cylinder is variable in a predefinable manner.
9. The hydropneumatic braking and return system according to claim
7, wherein the hydraulic control circuit includes a cooling
system.
10. The hydropneumatic braking and return system according to claim
7, wherein a plurality of the working cylinders are arranged as to
be distributed uniformly around a circumference of the gun
barrel.
11. The hydropneumatic braking and return system according to claim
7, and further comprising a central electronic control device
operatively arranged so as to activate the actuators of the
hydraulic control circuit.
12. The hydropneumatic braking and return system according to claim
11, wherein the electronic control device is operative to activate
the pressure limiting valve so that a substantially constant brake
force profile results during the recoil of the gun barrel.
Description
[0001] The invention relates to a hydropneumatic braking and return
system for barrel-recoil guns.
[0002] In barrel-recoil guns, the recoiling gun barrel is braked
after firing generally by a hydraulic barrel brake (cf. for example
Rheinmetall "Waffentechnisches Taschenbuch", 7.sup.th edition 1985
pages 440 ff.). In this case, a piston, which is connected to the
recoiling mass of the gun, is displaced in a fluid-filled brake
cylinder and the fluid which is displaced during the recoil is
pressed through a narrow throughflow cross section of the piston or
of the cylinder wall adjoining the piston. After completion of the
recoil, the recoiling mass is then pressed back again to the
starting position with the aid of a separate barrel returner. The
barrel returner is conventionally configured as a pneumatic,
hydropneumatic or mechanical system.
[0003] Drawbacks of the known systems consisting of a hydraulic
barrel brake and barrel returner include the fact that they are
mechanically highly complex in their construction. In order for
example to obtain, despite the varying recoil speed of the gun
barrel, a constant brake force profile which is required in barrel
brakes, the throughflow cross section is varied as a function of
distance in the known barrel brakes. This takes place, for example,
through an annular gap between the piston rod, which is hollow in
its configuration, and a stationary control rod having an axially
varying diameter.
[0004] In addition, in the known barrel brake and barrel returner
systems, varying shooting parameters, such as the different
pressure curves when different types of ammunition are used,
generally cannot easily be taken into account. On the contrary,
these cases each require complex adjustment tests or if appropriate
even the barrel brakes or barrel returners to be replaced.
[0005] It is already known from DE 198 32 495 C1 to use, in a
hydrodynamic gun damper having a fluid flow control rod, such as is
described in greater detail in DE 38 24 153 A1, a
magnetorheological or electrorheological damping medium, the
viscosity of which can be varied by a corresponding control device,
in order to take account of the braking behavior of barrel brakes
as a function of the various shooting parameters such as the type
of ammunition, the type of propellant, the elevation of the barrel,
the running direction of the barrel and temperature of the damping
medium.
[0006] Nevertheless, in this known barrel brake too, a relatively
complex mechanical construction of the barrel brake is required in
order to realize a throughflow cross section which is dependent on
the recoil path.
[0007] The invention is based on the object of disclosing a braking
and return system for barrel-recoil guns, which system is
mechanically much simpler in its construction than comparable known
systems and which allows changes in different shooting parameters
to be taken into account in a simple manner without it being
essential to alter the viscosity of the brake fluid for this
purpose.
[0008] According to the invention, this object is achieved by the
features of claim 1. The sub-claims disclose further, particularly
advantageous configurations of the invention.
[0009] The invention is based substantially on the notion of
dispensing with a specific brake cylinder having a control rod for
defining a throughflow cross section which is dependent on the
recoil path and of replacing the brake cylinder with a simple
working cylinder having a conventional working piston, the working
cylinder being connected to a hydraulic accumulator via an external
pressure limiting valve and a hydraulic control circuit. In this
case, the pressure limiting valve can be set manually to fixed
values or can be operated for example electronically/electrically
from a controller in such a way that preferably a substantially
constant brake force profile results during the recoil of the gun
barrel.
[0010] The hydraulic accumulator comprises a hydraulic cylinder in
which a separating piston separates a first chamber, which is
connected to the pressure limiting valve, from a second chamber,
which is filled with a prestressed gas, in such a way that during
the recoil movement of the gun barrel from its rest position to its
recoil end position, the displacement of the working piston presses
the displaced brake fluid from the working cylinder into the first
chamber via the adjustable pressure limiting valve and the gas in
the second chamber of the hydraulic accumulator is compressed as a
result of displacement of the separating piston. During relaxation
of the compressed gas, the brake fluid is then pressed back into
the working cylinder and causes the gun barrel to advance to its
rest position, thus obviating the need for a separate barrel
returner.
[0011] Preferably, the hydraulic control circuit comprises, in
addition to the pressure limiting valve, inter alia at least one
throttle valve with which the speed of the flow of brake fluid
which is pressed back from the first chamber of the hydraulic
accumulator into the working cylinder can be varied in a
predefinable manner.
[0012] In the system according to the invention, the working
cylinder and the working piston therefore serve both as the barrel
brake and as the barrel returner and heat compensating system. Both
the braking behavior and the speed of advance and the advance
braking can be controlled manually by the hydraulic control circuit
and/or automatically by a corresponding control device, so that the
system can easily be adapted inter alia also to different types of
ammunition.
[0013] As a result of the fact that a control rod and the
mechanical recoil path adjustment mechanism are dispensed with in
the brake cylinder, there is also no need for the complex
adjustment tests which are required in known comparable barrel
brakes and with which the sufficiently precise control profile and
also the preliminary computer design of the corresponding control
profile are found for the first time.
[0014] In addition, the system according to the invention has the
advantage that the working cylinder can be configured so as to be
much smaller and lighter than conventional brake cylinders. It is
therefore possible to integrate a plurality of working cylinders
into a weapon system in order to achieve more beneficial force
profiles in the force-diverting components. In this case, the
working cylinders can for example be arranged concentrically around
the gun barrel.
[0015] The hydraulic control circuit can be mounted on the gun.
However, it can for example also be arranged on or in the vehicle
carrying the gun. This can yield inter alia advantages with regard
to safety, the distribution of mass, maintenance and upkeep.
[0016] Preferably, the system according to the invention is of
modular construction, so that it can be used in a plurality of
types of weapon and an individual design (each weapon having its
own barrel brake) can be dispensed with. This offers inter alia
advantages in the logistics, development and certification of the
system according to the invention.
[0017] Unlike in known barrel brakes, in which, when the brake
fluid is changed, the change in density (and the thus altered
control profile) generally means that the control rod has to be
changed, this is not required in the system according to the
invention. On the contrary, in the system according to the
invention, merely the activation of the pressure limiting valve is
altered when the brake fluid is changed. This can take place for
example as a result of altered software of the electronic control
device activating the pressure limiting valve. The pressure
limiting valve is preferably always set to a specific pressure
(opening pressure). This can take place once from the max. system
pressure. This leads to different recoil paths for different shot
parameters (for example the size of the propellant, type of
bullets, elevation of the barrel). Alternatively, adjustment
immediately before each shot is possible. This allows the
corresponding value for the opening pressure of the valve to be set
depending on the ammunition selected. This value should preferably
have been determined beforehand. However, the entire recoil path
can be utilized in this case too and pressures which are as small
as possible are obtained.
[0018] If required, the hydraulic control circuit can additionally
also contain a cooling system, for example a heat exchanger, for
cooling the brake fluid which is heated during the recoil and
advance of the gun barrel.
[0019] Further details and advantages of the invention will emerge
from the following exemplary embodiment described with reference to
a FIGURE.
[0020] In the FIGURE, reference numeral 1 denotes a working
cylinder comprising a working piston 3 fastened to a piston rod 2.
A brake fluid 4 (for example oil) is contained in the working
cylinder 1. The piston rod 2 is connected, on its end remote from
the working piston 3, to the base piece 5 of a gun barrel 6
indicated by broken lines (recoiling mass of the gun) and the
working cylinder 1 to a cradle 7, also indicated by broken lines,
of the corresponding gun (non-recoiling mass).
[0021] The working cylinder 1 is connected to a hydraulic
accumulator 9 via a hydraulic control circuit 8 which is indicated
merely schematically. In this case, the control circuit 8 comprises
a pressure limiting valve 10 which can be controlled or regulated
by an electronic control device 11. The electronic control device
can for example be the fire control computer of the corresponding
weapon system.
[0022] The hydraulic accumulator 9 comprises a hydraulic cylinder
12 in which a separating piston 13 separates a first chamber 14,
which is connected to the hydraulic control circuit 8, from a
second chamber 16, which is filled with a prestressed gas 15 (for
example nitrogen).
[0023] During firing, the gun barrel 6 recoils from its rest
position illustrated in the FIGURE to its recoil end position in
the direction of the arrow 17. In this case, the working piston 3
is also displaced in the direction of the arrow 17 and the brake
fluid 4 thus displaced is pressed by the working cylinder 1 into
the first chamber 14 of the hydraulic accumulator 9 via the
adjustable pressure limiting valve 10, at which the back pressure
is produced, of the hydraulic control circuit 8. This causes a
displacement of the separating piston 13, so that the gas 15 in the
second chamber 16 of the hydraulic accumulator 9 is compressed
until the gun barrel 6 has reached its recoil end position.
[0024] After reaching the recoil end position of the gun barrel 6,
the gas 15 relaxes again and displaces the separating piston 13
until the gas 15 has relaxed to its initial pressure. As a result
of displacement of the separating piston 13, the brake fluid 4 is
pressed back out of the first chamber 14 of the hydraulic
accumulator 9 into the working cylinder 1 and the gun barrel 6 is
caused to advance to its rest position. In this case, the speed of
advance can be controlled or regulated manually using a throttle
valve 18 provided in the hydraulic control circuit 8 or by means of
the electronic control device 11.
[0025] A directional control valve which may be seen in the figure
and is denoted by reference numeral 19 is switched for the most
part only for the advance of the barrel. Beforehand, it prevents
brake oil from flowing away via the throttle 18. The throttle valve
18 is closed in its basic position and is then opened if the brake
pressure exceeds the system pressure (pressure accumulator
pressure).
[0026] If a plurality of working cylinders are used, the following
variants are alternatively possible: a plurality of working
cylinders and also one accumulator and one circuit, or a plurality
of working cylinders, a plurality of accumulators and one circuit,
or a plurality of working cylinders, accumulators pertaining
thereto and the associated circuit (as a unit=brake return
module).
[0027] The invention is obviously not limited to the exemplary
embodiment described hereinbefore. Thus, the hydraulic control
circuit can for example additionally contain also a cooling system,
for example a heat exchanger, for cooling the brake fluid which is
heated during the recoil and advance of the gun barrel. In this
case, the cooler, which will not be described in greater detail,
should preferably be incorporated into the line in which the lowest
pressure occurs (for example the current regulator line), so as to
minimize the size of the cooler.
[0028] In addition, the working cylinder can be provided both with
a "pulling" and with a "pressing" piston rod.
[0029] Furthermore, the pressure limiting valve does not
necessarily have to be activated in such a way as to produce a
constant brake force profile but rather, if desired, almost any
brake force profile can be generated by appropriate activation of
the pressure limiting valve.
* * * * *