WO1998001717A1

WO1998001717A1 - Apparatus for moving a barrel assembly of a gun

Info

Publication number: WO1998001717A1
Application number: PCT/NL1997/000375
Authority: WO
Inventors: Ernst Johann Heinrich MÜLLER
Original assignee: Denel (Proprietary) Limited; Octrooibureau Kisch N.V.
Priority date: 1996-07-05
Filing date: 1997-07-01
Publication date: 1998-01-15
Also published as: AU3360297A

Abstract

This invention provides a gun (1) of the type having a base (2), a barrel assembly (4) movable relative to the base (2) between an in-battery position and a recoiled position, and biasing means in the form of counter recoils (12, 14) for biasing the barrel assembly (4) in the direction of the in-battery position as indicated by arrow B. The gun (1) is characterised in that it further includes external displacement means for urging the barrel assembly (4) towards the recoiled position, when no projectile is fired, against the biasing action of the counter recoils (12, 14) as indicated by arrow C. A hydraulic pump builds pressure up on one side of recoil piston. Piston moves to the rearward recoil position. Use: testing, and/or misfire extraction, maintenance or repair, transport.

Description

_Title: Apparatus for moving a barrel assembly of a gun.

INTRODUCTION AND BACKGROUND TO THE INVENTION

This invention relates to a gun such as a cannon or the like and to a method

and means for moving a barrel assembly of such a gun between an in-

battery position and a recoiled position.

5

A gun such as a cannon or the like usually comprises a barrel assembly

mounted on a base and movable relative to the base between an in-battery

position and a recoiled position. At least one buffer is usually connected

between the barrel assembly and the base to retard motion of the barrel

10 assembly in the direction of the recoiled position, during recoil after firing

the gun The gun is usually provided with a biasing means for biasing the

barrel assembly towards the in-battery position. The biasing means is

usually in the form of one or more counter recoils comprising a piston and

cylinder assembly which defines a chamber on each side of the piston. One

15 chamber is pressurised with gas which is compressed when the barrel

assembly moves towards the recoiled position and the other chamber is

provided with a vent to atmosphere. After reaching the recoiled position,

the compressed gas expands to move the barrel assembly back to the in-

battery position.

•20

A disadvantage of the above described gun is that when the barrel

assembly needs to be moved to the recoiled position against the bias of the counter recoils without firing the gun, for example when maintenance of the

gun is required, an external, relatively heavy, hydraulic piston operated jack

has to be connected between the base and the barrel assembly, and the

barrel assembly moved to the recoiled position by manual operation of the

hydraulic piston operated jack. Some of the disadvantages of such

operation are that an external hydraulic piston operated jack may not

always be at hand; the method is relatively slow; and it often requires the

use of an additional vehicle and the efforts of more than one person to bring

the jack into position.

When a gun has misfired, the misfired charge may ignite at any stage and

may present a danger to operators of the gun. It is thus necessary to

remove the misfired charge from the gun by moving the barrel assembly of

the gun to the recoiled position from a remote location. Another

disadvantage of the hydraulic piston operated jack is that it cannot be

operated easily from a remote location, if at all.

OBJECT OF THE INVENTION

It is accordingly an object of the present invention to provide a gun such as

a cannon or the like having integral displacement means for moving a barrel

assembly of the gun between an in-battery position and a recoiled position with which the aforesaid disadvantages can be overcome or at least

minimised.

SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided a gun of the

type having

a base;

a barrel assembly movable relative to the base between an in-battery

position and a recoiled position; and

- at least one biasing means for biasing the barrel assembly in the

direction of the in-battery position;

characterised in that the gun further comprises

integral displacement means for urging the barrel assembly towards

the recoiled position against the biasing action of said biasing means.

Further according to the invention, the biasing means is in the form of at

least one compressible ram device connected between the base and the

barrel assembly and having expanding means such as compressible gas or

a compression spring.

In a preferred arrangement the ram device comprises a piston and cylinder

assembly defining a first pressure chamber on one side of the piston and a second pressure chamber on the other side of the piston, with the first

pressure chamber being pressurised by compressible fluid so as to bias the

piston in a first direction relative to the cylinder to bias the barrel assembly

in the direction of the in-battery position.

The integral displacement means may comprise the ram device together

with a source of pressurised fluid for pressurising the second pressure

chamber to overcome the pressure in the first pressure chamber to urge the

piston in a second opposite direction and thus to cause the barrel assembly

to move towards the recoiled position.

Further according to the invention the pressurised fluid is hydraulic fluid and

the pressure source comprises a hydraulic pump.

The pump may be energised by a motor and the motor may be energised by

a source of hydraulic fluid for operating an existing hydraulic circuit of the

gun.

Further according to the invention, the gun comprises a control means for

controlling the pressurisation of the second pressure chamber.

Preferably the control means is operable from a remote location. The hydraulic circuit may further include a reservoir for hydraulic fluid and

a number of valves for controlling flow of hydraulic fluid in the circuit.

According to another aspect of the invention there is provided a method of

moving a barrel assembly of a gun such as a cannon or the like between an

in-battery position and a recoiled position, the method including the steps

of:

providing a ram device for biasing the barrel assembly towards the

in-battery position; and

- reversing the biasing action of the ram device to move the barrel

assembly in the direction of the recoiled position.

The ram device may include a piston and cylinder assembly having a first

pressure chamber on one side of the piston and a second pressure chamber

on the other side of the piston, the first pressure chamber being pressurised

by a compressible gas which bias the barrel assembly towards the in-

battery position and the method may include the further step of reversing

the bias by pressurising the second pressure chamber to overcome the

pressure in the first pressure chamber. The gun may include a controller for controlling the pressurisation of the

second pressure chamber and the method may include the further step of

operating the controller from a remote location.

The controller may be operated by an electromagnetic signal.

The method may include the further step of lowering the pressure in the

second chamber so that the barrel assembly is moved back to the in-battery

position under the bias of the gas in the first pressure chamber.

0

According to yet another aspect of the invention there is provided apparatus

for moving a barrel assembly of a gun such as a cannon or the like between

an in-battery position and a recoiled position, comprising:

a ram device connected between the barrel assembly and a base of

5 the gun, the ram device comprising a piston and cylinder assembly

having a first pressure chamber on a first side of the piston and a

second pressure chamber on the other side of the piston, the first

chamber being pressurised by a compressible fluid for biasing the

barrel assembly in the direction of the in-battery position; and

0 - a source of pressurised working fluid for pressurising the second

pressure chamber against the pressure in the first pressure chamber to reverse the biasing action of the ram device and thus to move the

barrel assembly in the direction of the recoiled position.

BRIEF DESCRIPTION OF THE DIAGRAM

A preferred embodiment of the invention will now be described, by way of

example only, with reference to the accompanying diagram which is a

schematic representation of a gun such as a cannon or the like according

to a preferred embodiment of the invention having integral displacement

means for moving a barrel assembly of the gun between an in-battery and

a recoiled position.

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

Referring to the diagram, a schematic representation of a gun such as a

cannon or the like according to a preferred embodiment of the invention is

generally designated by reference numeral 1 . The gun 1 is of the type

comprising a base 2; a barrel assembly 4 movable relative to the base 2 as

indicated by arrow A, between an in-battery position and a recoiled

position; a buffer (not shown) for retarding motion of the barrel assembly

in the direction of the recoiled position during recoil after firing the gun; and

a biasing means 1 0 for biasing the barrel assembly 4 in the direction of the

in-battery position. The biasing means 1 0 comprises a ram device in the

form of a pair of counter recoils 1 2 and 14 connected between the base 2 and the barrel assembly 4. Thusfar the gun 1 is similar to conventional guns

of this type.

The counter recoils 1 2 and 1 4 are adapted to provide part of an integral

displacement means for urging the barrel assembly 4 towards the recoiled

position against the biasing action of the biasing means 10.

The counter recoils 1 2 and 1 4 comprise assemblies of pistons 1 6 and

cylinders 1 8, defining first pressure chambers 1 9 and 20 on one side of the

pistons 1 6 and defining second pressure chambers 21 and 22 on the other

side of the pistons 1 6, respectively. The first pressure chambers 1 9 and 20

are pressurised by compressible gas so as to bias the pistons 1 6 in a first

direction indicated by arrow B, thus to bias the barrel assembly 4 in the

direction of the in-battery position.

The gun 1 further includes an auxilary power unit providing a source of

hydraulic pressurised working fluid along a hydraulic circuit generally

designated by reference numeral 24. The hydraulic circuit 24 connects the

pressurised working fluid to the second pressure chambers 21 and 22 and

includes a control means 25 for controlling pressurisation of the second

pressure chambers 21 and 22. Pressurisation of the second pressure

chambers 21 and 22 urges the pistons 1 6 in a second opposite direction indicated by arrow C, against the pressure in the first chambers 1 9 and 20,

thus to move the barrel assembly 4 in the direction of the recoiled position.

The pressurised working fluid is provided by a pump 26 and the hydraulic

circuit 24 further includes a motor 28 for driving the pump 26; a reservoir

27 for hydraulic fluid; a pressure control valve 35; a non-return valve 29;

and two control valves 30. 1 and 30.2. The controller 25 is operable from

a remote location by an electromagnetic signal or the like.

In use, the controller 25 is operated from a remote location to open the

control valves 30. 1 and 30.2 and the second pressure chambers 21 and 22

are thus pressurised to overcome the pressure in the first pressure

chambers 1 9 and 20 to reverse the biasing action of the counter recoils 1 2

and 1 4. The barrel assembly 4 is thus moved in the direction of arrow C

to the recoiled position.

Whenever the barrel assembly 4 is to be moved back in the direction of

arrow B to the in-battery position, the pressure control valve 35 is opened

to relieve the pressure inside the second chambers 21 and 22, so that the

barrel assembly 4 moves to the in-battery position under the biasing action

of the pressurised gas in the first pressure chambers 1 9 and 20. It will be appreciated that a barrel assembly of a gun according to the

invention can hence be moved to the recoiled position with relative ease

from a remote location by said electromagnetic signal or the like.

It will be appreciated that a large number of variations in detail are possible

with a gun according to the invention such as a cannon or the like having

integral displacement means for moving a barrel assembly of the gun

between an in-battery position and a recoiled position, without departing

from the scope and/or spirit of the appended claims.

Claims

1 . A gun of the type having a base, a barrel assembly movable relative

to the base between an in-battery position and a recoiled position,

and at least one biasing means for biasing the barrel assembly in the

direction of the in-battery position, characterised in that the gun

comprises integral displacement means for urging the barrel assembly

towards the recoiled position against the biasing action of said

biasing means.

2. A gun according to claim 1 wherein the biasing means is in the form

of at least one compressible ram device connected between the base

and the barrel assembly and having expanding means such as

compressible gas or a compression spring.

3. A gun according to claim 2 wherein the ram device comprises a

piston and cylinder assembly defining a first pressure chamber on

one side of the piston and a second pressure chamber on the other

side of the piston, with the first pressure chamber being pressurised

by compressible fluid so as to bias the piston in a first direction

relative to the cylinder to bias the barrel assembly in the direction of

the in-battery position.

4. A gun according to claim 3 wherein the integral displacement means

comprises the ram device together with a source of pressurised fluid

for pressurising the second pressure chamber to overcome the

pressure in the first pressure chamber to urge the piston in a second

opposite direction and thus to cause the barrel assembly to move

towards the recoiled position.

5. A gun according to claim 4 wherein the pressurised fluid is hydraulic

fluid and the pressure source comprises a hydraulic pump.

6. A gun according to claim 5 wherein the pump is energised by a

motor and the motor is energised by a source of hydraulic fluid for

operating an existing hydraulic circuit of the gun.

7. A gun according to claim 6 which includes a control means for

controlling the pressurisation of the second pressure chamber.

8. A gun according to claim 7 wherein the control means is operable

from a remote location.

9. A gun according to claim 8 wherein the hydraulic circuit includes a

reservoir for hydraulic fluid and a number of valves for controlling

flow of hydraulic fluid in the circuit.

10. A method of moving a barrel assembly of a gun such as a cannon or

the like between an in-battery position and a recoiled position, the

method including the steps of:

providing a ram device for biasing the barrel assembly towards

the in-battery position; and

- reversing the biasing action of the ram device to move the

barrel assembly in the direction of the recoiled position.

1 . A method according to claim 10 wherein the ram device includes a

piston and cylinder assembly having a first pressure chamber on one

side of the piston and a second pressure chamber on the other side

of the piston, the first pressure chamber being pressurised by a

compressible gas which bias the barrel assembly towards the in-

battery position and wherein the method includes the further step of

reversing the bias by pressurising the second pressure chamber to

overcome the pressure in the first pressure chamber.

2. A method according to claim 1 1 wherein the gun includes a

controller for controlling the pressurisation of the second pressure

chamber and wherein the method includes the further step of

operating the controller from a remote location.

3. A method according to claim 1 2 wherein the controller is operated by

an electromagnetic signal.

4. A method according to any one of claims 1 1 to 1 3 which includes

the further step of lowering the pressure in the second chamber so

that the barrel assembly is moved back to the in-battery position

under the bias of the gas in the first pressure chamber.

5. Apparatus for moving a barrel assembly of a gun such as a cannon

or the like between an in-battery position and a recoiled position,

comprising:

a ram device connected between the barrel assembly and a

base of the gun, the ram device comprising a piston and

cylinder assembly having a first pressure chamber on a first

side of the piston and a second pressure chamber on the other

side of the piston, the first chamber being pressurised by a compressible fluid for biasing the barrel assembly in the

direction of the in-battery position; and

a source of pressurised working fluid for pressurising the

second pressure chamber against the pressure in the first

pressure chamber to reverse the biasing action of the ram

device and thus to move the barrel assembly in the direction

of the recoiled position.