IMPROVEMENTS IN CARRIAGES FOR NAVAL AND FIELD ORDNANCE
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said Thorsten Nordenfelt at
the Office of the Commissioners of Patents on the 6th March 1882.
THORSTEN NORDENFELT of Saint Swithins Lane in the City of London
"IMPROVEMENTS IN CARRIAGES FOR NAVAL AND FIELD ORDNANCE."
The object of this improvement is to check the recoil from guns, and to carry
them quickly back again to firing position with moderate rebound.
To obtain this I combine a spring with a hydraulic buffer or with a friction
arrangement.
In the first case I put the spring or springs inside the hydraulic cylinder in such
a way that they are acted upon direct by the hydraulic piston The liquid in the
cylinder is on both sides of the piston and is during the action of the recoil, forced
from one side of the piston to the other through specially made passages. This
passages consist of grooves along the inner surface of the cylinder and their
combined sectional area may either be constant over the whole stroke, or varying
for the purpose of better regulating the fluctuation of pressure during the move-
ment of the piston as desired the variation of the area of the grooves is obtained
by making them more or less deep or wide or by increasing or diminishing their
number at certain parts of the length of the cylinder.
The action of this arrangement may readily be understood as follows:-
When the shot is fired the piston forces the liquid from one side to the other
through the passages and at the same time compresses the spring, thus taking up
the recoil by the hydraulic action and by the spring combined. When the recoil
is partly absorbed by the hydraulic resistance, and partly stored up in the spring
the latter carries the piston back again with a rapidity moderated by the resistance
of the liquid and thus brings the gun again in firing position without any injurious
shock to the carriage.
In the second case instead of the hydraulic cylinder I propose to combine the
spring with an ordinary friction arrangement as clamps cramped on iron bars or a
screw with high pitch going through a round nut which is acted upon by a brake.
Either of these arrangements can be placed direct on a sliding carriage or on
one end of a lever the other end of which holds the trunnions of the gun.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thorsten Nordenfelt in the Great Seal Patent Office on the
5th September 1882.
THORSTEN NORDENFELT of Saint Swithins Lane in the City of London
"IMPROVEMENTS IN CARRIAGES FOR NAVAL AND FIELD ORDNANCE
"
The object of this improvement is to check the recoil from guns, and to carry
them quickly back again to firing position with moderated rebound.
To obtain this I combine a spring with a hydraulic buffer, I put the spring or
springs inside the hydraulic cylinder in such a way that they are acted upon direct
by the hydraulic piston. The liquid in the cylinder is on both sides of the piston,
and is during the action of the recoil forced from one side of the piston to the
other through specially made passages. These passages consist of grooves along
the inner surface of the cylinder, and their combined sectional area may either be
constant over the whole stroke, or varying for the purpose of better regulating the
fluctuation of pressure during the movement of the piston; as described the
variation of the area of the grooves is obtained by making them more or less deep
or wide, or by increasing or diminishing their number at certain parts of the
length of the cylinder.
The action of this arrangement may readily be understood as follows:-
When the shot is fired the piston forces the liquid from one side to the other
through the passages and at the same time, compresses the spring thus taking up
the recoil by the hydraulic action and by the spring combined. When the recoil
is partly absorbed by the hydraulic resistance, and partly stored up in the spring,
the latter carries the piston back again with a rapidity moderated by the resistance
of the liquid and thus brings the gun again in firing position without any injurious
shock to the carriage.
In order that my said Invention may be most fully understood and readily
carried into effect I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a side elevator partly in section of a gun upon a pivot carriage
to which my combined spring and hydraulic buffer is applied.
Figure 2 is a rear elevation, and Figure 3 is a plan of the same. The trunnions
of the gun are carried upon a lever a, of which the fulcrum is at a¹. so that the
lower end of the lever is drawn forward by the recoil. The lever a. is here jointed
to the piston rod b. of a piston c. the piston rod is surrounded by the spiral springs
d. d. and e. is a disc through which the rod passes freely. f is a cylinder in which
the piston, the springs and the disc are contained. The end cover of the cylinder f
is secured to the gun carriage by a bolt g. on which the cylinder is able to rock
Blightly to accommodate itself to the position of the lever a. At the front end of
the cylinder there is a gland containing a cupped leather f¹, to retain the oil or
other liquid with which the cylinder is filled. ff. are grooves within the
cylinder to permit the oil or liquid to pass the piston, they become fewer and
narrower as the fore end of the stroke of the piston is approached.
Other parts of the gun carriage and the gun are clearly shewn in the Drawings
but they form no part of the invention secured to me by this Patent.
Having thus described the nature of the said Invention and the manner of

page_text: performing the same I would have it understood that I claim my improvements in
carriages for naval and field ordnance consisting in providing them with my
combined spring and hydraulic buffer substantially as described.
In Witness whereof I the said Thorsten Nordenfelt have hereunto set my
hand and seal this twenty eighth day of August in the year of our
Lord One thousand eight hundred and eighty two.
THORSTEN NORDENFELT. (L.S.)