Improved Means for Compressing Air or Gases, Especially Applicable for Impelling, Ejecting, or Propelling High Explosive Projectiles and the like.
Year: 1889

page_text: Date of Application, 14th June, 1889
Complete Specification Left, 13th Mar., 1890-Accepted. 7th June,
1890
PROVISIONAL SPECIFICATION.
Improved Means for Compressing Air or Gases, Especially Applicable
for Impelling, Ejecting, or Propelling High Explosive Projectiles
and the like.
T
BENJAMIN HOWARTH THWAITE of 37 Victoria Street Liverpool in the County of
Lancaster Civil Engineer do hereby declare the nature of this invention to be as
follows:-
My invention consists of an improved means for compressing air or gases especially
adapted for impelling ejecting or propolling high explosive projectiles, and the like;
and consists as follows; I employ an explosive medium containing its own agent of
oxidation such as gun cotton gunpowder dynamite and the like, or it may be an agent
requiring the addition of oxygen, such as liquid or gaseous hydrocarbons, carbon-
monoxide or any other gaseous solid or liquid agent that oxidises and by its oxidation
produces heat rapidly.
י
This agent I utilise for forcing forward the piston of an air or gaseous fluid
cylinder, the said piston having a piston rod passing through its centre and which
said rod serves for allowing or enabling the air or other gas compressed by reason of
the movement of the piston, to escape into an annular chamber, from which it enters
the end of the tube of the gun, expelling from the said tube any obstacle-such as a
projectile-shot or a piston-with a velocity depending on the relative compression of
the air and the size of the tube in which its expansion can take place-by this
arrangement, projectiles containing high explosives can be safely ejected or shot from
the tube or tubes if the arrangement is utilised for warlike or other similar purposes-
but I may utilise the power stored in the compressed air for other and industrial
purposes.
Referring to figure 1 which shews a longitudinal section of my invention when
applied for ordnance purposes or for impelling high explosive projectiles-and
figure 2 shews a side elevation. A is the explosive chamber. B is the expanding
chamber. C is the piston. D the hollow rod-which allows the compressed air and
gases to escape into the gun tube E. expelling impelling and ejecting the explosive
projectile F.
The arrangement for effecting the escape of the compressed air after the piston is
forced forward by the explosive gases which enter into the cylinder through the
hollow part G of the piston is as follows."
When the piston has been forced forward until the air is highly compressed it
opens a port H and the compressed gas escapes through the hollow part 1 of the
piston rod. The same arrangement of hollow part of piston rod allows a small opening
in the explosive chamber to be opened, so that there is a limit set on the pressure
developed by the explosion. At the front end of piston and around the front piston
rod D, I provide a steel spring coil that forces back the piston to the back end ready
for a new charge immediately the valve K is opened, which allows air to enter on
one side of the piston and the residual compressed gases contained on the other side
of piston to escape.
This valve K I may make of any suitable construction.
The valve arrangement shewn is of the cylinder type, with a small bore passage L
crossing its axis, which bore can be brought opposite corresponding passages: M in the
side of the cylinder and having passages N running right and left to the ends of the
cylinder.
which'in of course closed during the explosion and

page_text: The openings P in explosive chamber A allow the excess of explosive charge
to escape and fix a safety limit to the pressure established by the explosive
action.
J
COMPLETE SPECIFICATION.
Improved Means for Compressing Air or Gases, Especially Applicable
for Impelling, Ejecting, or Propelling High Explosive Projectiles
and the like.
I BENJAMIN HOWARTH THWAITE of 37 Victoria Street Liverpool in the County of
Lancaster, Civil Engineer do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
My invention consists of improved means for compressing air or gases especially
adapted for impelling, ejecting or propelling bigh explosive projectiles, and the like,
and consists as follows. I employ an explosive medium, containing its own agent of
oxidation, such as gun cotton, gunpowder, dynamite, and the like, or it may be an
agent requiring the addition of oxygen, such as liquid, or gaseous hydrocarbons,
carbon monoxide or any other gaseous, solid or liquid agent that oxidises, and by its
oxidation produces heat rapidly.
This agent utilize for forcing forward the piston of an air or gaseous fluid
cylinder, the said piston having a piston rod passing through its centre, and which
said rod serves for allowing or enabling the air or other gas compressed by reason of
the movement of the piston, to escape into an annular chamber, from which it enters
the end of the tube of the gun, expelling from the said tube any obstacle-such as a
projectile, shot or a piston-with a velocity depending on the relative compression
of the air, and the size of the tube in which its expansion can take place. By
this arrangement projectiles, containing high explosives can be safely ejected, or shot
from the tube or tubes of a gun. If the arrangement is utilized for warlike or
other similar purposes; but I may utilize the power stored in the compressed air
for other and industrial purposes.
Referring to Figure 1 Sheet 1 of drawings which shows a longitudinal section
of my invention when applied for ordnance purposes, or for impelling high
explosive projectiles, and Figure 2 shows a plan. A is the explosive chamber;
B is the expanding and air compressing chamber; C is the piston; D the hollow
rod which allows the compressed air and gases to escape into the gun tube E;
expelling, impelling, and ejecting the explosive projectile F.
The arrangement for effecting the escape of the compressed air, after the piston is
forced forward by the explosive gases which enter into the cylinder through the
hollow part G of the piston, is as follows.
When the piston has been forced forward until the air is highly compressed, it
opens a port H, and the compressed gas escapes through the hollow part of the piston
rod. The same arrangement of hollow part of piston rod, allows small openings-I in
the explosive chamber to be opened, so that there is a limit set on the pressure
developed by the explosion. At the front end of piston and around the front piston
rod D, I provide a steel spring coil J that forces back the piston to the back end,
ready for a new charge immediately the valves K are opened, which allows air to
enter on one side of the piston and the residual compressed gases contained on the
other side of piston, to escape.
This valve K I may make of any suitable construction.
The valve arrangement shown is of the cylinder type, with a small bore passage L
orossing its axis, which bore can be brought opposite corresponding passages M in the
side of the cylinder, and having passages N running right and left to the ends of the

page_text: A lever O, actuates the valve, which is of course closed during the explosion and
opened afterwards. The openings I in explosive chamber A allow the excess of
explosive charge to escape, and fix a safety limit to the pressure established by the
explosive action.
Referring to Sheet 2 of drawings, Figures 3 & 4 shew longitudinal sections of
another and simpler modification of my invention. Referring in the first instance to
Figure 3, Q is the explosive chamber, the hollow piston rod R, and piston S serves for
the compressure of the air, in cylinder T, in a manner herein described.
The compressed air forces forward and ejects the projectile U, at a high velocity
through and from the bore of the gun. I provide a simple keybar arrangement for
drawing back the piston to the rear end or beginning of the stroke end of piston. The
keybar is inserted into the explosive chamber, at the breach-piece end.
In the arrangement shewn in Figure 4, the front end of piston is provided with a
piston rod W having an enlarged head X.
Working closely in a chamber Y between the air compressional cylinder, & the
box of the gun. At the front end of chamber Y, and between it and the bore of
the gun, is an enlarged space Z, by which the compressed air can thus escape from
the chamber Y, and enter the bore of the gun, ejecting out of this gun the
projectile.
It will be seen by this last arrangement that a definite storage of compressed
air can be obtained before it is allowed to escape forward into the bore of the
gun.
Figure 5 shews another adaptation of my invention. The air, or other gas under
compression, is stored in a reservoir, from which it can be distributed to various guns,
or for industrial purposes.
Referring to Figure 5 shewing a general sectional view of this arrangement, an
explosion chamber 2 is provided at each end of the cylinder 3. But this duplex
arrangement is not absolutely necessary as will be understood. The air compressed
in the cylinder escapes through escape pipe 4, and passes through a distributing
valve 5, and forces open a nonreturn valve 6 in the air storage cylinder 7.
The distributing valve allows the products of explosive combustion to escape; but
of course when required, the products of combustion as well as the compressed air,
may be allowed to enter the compressed air storage chamber.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same may be performed, I hereby declare that what I
claim is :-
1st The compression of air in a cylinder, by means of a piston propelled or
projected by the combustion of an explosive, whether solid, liquid or gaseous, substan-
tially as herein shewn and described.
2nd: The combination of an explosive chamber and an air compressing cylinder,
with a piston rod and piston working in combination substantially as herein.
described.
3rd-The arrangement or application by which the explosive gases expand into a
larger cylinder as herein shewn and described.
4th: The general arrangement shewn in Figures 1, 2, 3, & 4, and herein described
by which the compressed air is utilized for forcing, impelling and projecting explosive
projectiles from the bore of a gun.
5th-The arrangement for allowing the escape of the residual compressed and
explosive gases from the compressive cylinder substantially as herein shewn and
described.
Doted this 19th day of March 1890
B. H. THWAITE..